Internet basic

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Internet users around the globe

Internet users around the globe are facing slowed-down service, thanks to what's being called the biggest cyberattack in history.
The prolonged denial-of-service assault is targeting The Spamhaus Project, a European spam-fighting group that has gone after CyberBunker, a data-storage company that offers to host any content "except child porn and anything related to terrorism."
The organization has been in a long-running feud with CyberBunker and claims spammers use it as a host from which to spray junk mail across the Web.
Internet security firm CloudFlare said Spamhaus contacted it last week, saying it had been hit with an attack big enough to knock its site offline.
Security experts say the attack uses more sophisticated techniques than most DDoS (distributed denial of service) attacks and targets the Web's infrastructure, which has led to other sites performing slowly.


It's the biggest attack we've seen," Matthew Prince, CloudFlare's CEO, told CNN.
The FBI is involved in the investigation into the cyberattack on Spamhaus, though a bureau spokesman didn't provide any details on the FBI's role or the scope of the probe.
The Spamhaus Project is a nonprofit organization that patrols the Internet for spammers and publishes a list of Web servers those spammers use. According to Prince, the group may be responsible for up to 80% of all spam that gets blocked. This month, the group added CyberBunker to its blacklist.
"While we don't know who was behind this attack, Spamhaus has made plenty of enemies over the years," Prince wrote in a blog post. "Spammers aren't always the most lovable of individuals, and Spamhaus has been threatened, sued and DDoSed regularly."
In a DDoS attack, computers flood a website with requests, overwhelming its servers and causing it to crash or become inaccessible for many users.
One way to defend against those attacks, Prince said, is to deflect some of the traffic targeted at a single server onto a bunch of other servers at different locations. That's what happened in this case, and why Web users experienced some slowdowns on other sites.
He told CNN the last big wave of the attack hit Tuesday morning, but that he doesn't "live under the illusion" that there won't be more.
For its part, CyberBunker isn't taking credit for the attack. But the Dutch company, housed in a former NATO nuclear bunker, isn't shying away, either.
"This here is the internet community puking out SpamHaus," CyberBunker founder Sven Olaf Kamphuis told CNN. "We've had it with the guys ... . What we see right here is the internet puking out a cancer."
He said the owners of various websites got together on a Skype chat and hatched the plans for the attack. He says that StopHaus, a group organized to support CyberBunker in the dispute, ceased the attack after three days but that other hackers and activists kept it up after that.
Kamphuis and other critics say that Spamhaus oversteps its bounds and has essentially destroyed innocent websites in its spam-fighting efforts.
"Spamhaus itself is a more urgent danger" than spam, Kamphuis told CNN. "Pointing at websites and saying they want it shut down and then they get it shut down without any court order. That is a significantly larger threat to internet and freedom of speech and net neutrality than anything else."
Vincent Hanna, a researcher with The Spamhaus Project, said the group's record speaks for itself. He said the project has existed for over 12 years and its data is used to protect more than 1.7 billion e-mail accounts worldwide.
"We have 1.7 billion people looking over our shoulders to make sure we do our job right," he said. "If we start blocking things they want, they won't use our data any more."
He emphasized that Spamhaus doesn't have the power to block e-mail from anyone -- it merely makes its data available for service providers and other Web companies to use.
Hanna said Spamhaus experienced its first denial-of-service attack in 2003.
"This has been the biggest for us," he said, "but certainly not the first one."
Cloudflare's Prince said denying access to a website through cyberattacks is the truest assault on Web freedom.
"Our role is to allow the internet to achieve what it aspires to -- that anyone, anywhere can publish any piece of information and make it accessible to anyone, anywhere else in the world," he said. "It's blatant censorship.
"Whether Spamhaus is a good organization or a bad organization is irrelevant to me. We protect American financial institutions, which some people think are evil, and we protect WikiLeaks, which some people think are evil."

From Gopher to the WWW of internet

One of the most promising user interface paradigms during this period was hypertext. The technology had been inspired by Vannevar Bush's "Memex"and developed through Ted Nelson's research on Project Xanadu and Douglas Engelbart's research on NLS.Many small self-contained hypertext systems had been created before, such as Apple Computer's HyperCard (1987). Gopher became the first commonly used hypertext interface to the Internet. While Gopher menu items were examples of hypertext, they were not commonly perceived in that way.


This NeXT Computer was used by Sir Tim Berners-Lee at CERN and became the world's first Web server.
In 1989, while working at CERN, Tim Berners-Lee invented a network-based implementation of the hypertext concept. By releasing his invention to public use, he ensured the technology would become widespread.[86] For his work in developing the World Wide Web, Berners-Lee received the Millennium technology prize in 2004. One early popular web browser, modeled after HyperCard, was ViolaWWW.

A turning point for the World Wide Web began with the introduction of the Mosaic web browser[89] in 1993, a graphical browser developed by a team at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign (NCSA-UIUC), led by Marc Andreessen. Funding for Mosaic came from the High-Performance Computing and Communications Initiative, a funding program initiated by the High Performance Computing and Communication Act of 1991 also known as the Gore Bill.[90] Mosaic's graphical interface soon became more popular than Gopher, which at the time was primarily text-based, and the WWW became the preferred interface for accessing the Internet. (Gore's reference to his role in "creating the Internet", however, was ridiculed in his presidential election campaign. See the full article Al Gore and information technology).
Mosaic was eventually superseded in 1994 by Andreessen's Netscape Navigator, which replaced Mosaic as the world's most popular browser. While it held this title for some time, eventually competition from Internet Explorer and a variety of other browsers almost completely displaced it. Another important event held on January 11, 1994, was The Superhighway Summit at UCLA's Royce Hall. This was the "first public conference bringing together all of the major industry, government and academic leaders in the field [and] also began the national dialogue about the Information Superhighway and its implications."
24 Hours in Cyberspace, "the largest one-day online event" (February 8, 1996) up to that date, took place on the then-active website, cyber24.com. It was headed by photographer Rick Smolan.[94] A photographic exhibition was unveiled at the Smithsonian Institution's National Museum of American History on January 23, 1997, featuring 70 photos from the project.

e-mail, Simple Mail Transfer Protocol, and Usenet in internet

e-mail, Simple Mail Transfer Protocol, and Usenet
Email is often called the killer application of the Internet. However, it actually predates the Internet and was a crucial tool in creating it. Email started in 1965 as a way for multiple users of a time-sharing mainframe computer to communicate. Although the history is unclear, among the first systems to have such a facility were SDC's Q32 and MIT's CTSS.

The ARPANET computer network made a large contribution to the evolution of email. There is one report[82] indicating experimental inter-system email transfers on it shortly after ARPANET's creation. In 1971 Ray Tomlinson created what was to become the standard Internet email address format, using the @ sign to separate user names from host names.

A number of protocols were developed to deliver messages among groups of time-sharing computers over alternative transmission systems, such as UUCP and IBM's VNET email system. Email could be passed this way between a number of networks, including ARPANET, BITNET and NSFNET, as well as to hosts connected directly to other sites via UUCP. See the history of SMTP protocol.
In addition, UUCP allowed the publication of text files that could be read by many others. The News software developed by Steve Daniel and Tom Truscott in 1979 was used to distribute news and bulletin board-like messages. This quickly grew into discussion groups, known as newsgroups, on a wide range of topics. On ARPANET and NSFNET similar discussion groups would form via mailing lists, discussing both technical issues and more culturally focused topics (such as science fiction, discussed on the sflovers mailing list).
During the early years of the Internet, email and similar mechanisms were also fundamental to allow people to access resources that were not available due to the absence of online connectivity. UUCP was often used to distribute files using the 'alt.binary' groups. Also, FTP e-mail gateways allowed people that lived outside the US and Europe to download files using ftp commands written inside email messages. The file was encoded, broken in pieces and sent by email; the receiver had to reassemble and decode it later, and it was the only way for people living overseas to download items such as the earlier Linux versions using the slow dial-up connections available at the time. After the popularization of the Web and the HTTP protocol such tools were slowly abandoned.

Search engine (computing)

 Search engine (computing)
Even before the World Wide Web, there were search engines that attempted to organize the Internet. The first of these was the Archie search engine from McGill University in 1990, followed in 1991 by WAIS and Gopher. All three of those systems predated the invention of the World Wide Web but all continued to index the Web and the rest of the Internet for several years after the Web appeared. There are still Gopher servers as of 2006, although there are a great many more web servers.
As the Web grew, search engines and Web directories were created to track pages on the Web and allow people to find things. The first full-text Web search engine was WebCrawler in 1994. Before WebCrawler, only Web page titles were searched. Another early search engine, Lycos, was created in 1993 as a university project, and was the first to achieve commercial success. During the late 1990s, both Web directories and Web search engines were popular—Yahoo! (founded 1994) and Altavista (founded 1995) were the respective industry leaders. By August 2001, the directory model had begun to give way to search engines, tracking the rise of Google (founded 1998), which had developed new approaches to relevancy ranking. Directory features, while still commonly available, became after-thoughts to search engines.
Database size, which had been a significant marketing feature through the early 2000s, was similarly displaced by emphasis on relevancy ranking, the methods by which search engines attempt to sort the best results first. Relevancy ranking first became a major issue circa 1996, when it became apparent that it was impractical to review full lists of results. Consequently, algorithms for relevancy ranking have continuously improved. Google's PageRank method for ordering the results has received the most press, but all major search engines continually refine their ranking methodologies with a view toward improving the ordering of results. As of 2006, search engine rankings are more important than ever, so much so that an industry has developed ("search engine optimizers", or "SEO") to help web-developers improve their search ranking, and an entire body of case law has developed around matters that affect search engine rankings, such as use of trademarks in metatags. The sale of search rankings by some search engines has also created controversy among librarians and consumer advocates.
On June 3, 2009, Microsoft launched its new search engine, Bing. The following month Microsoft and Yahoo! announced a deal in which Bing would power Yahoo! Search.

File sharing of internet

File sharing , Peer-to-peer file sharing , and Timeline of file sharing
Resource or file sharing has been an important activity on computer networks from well before the Internet was established and was supported in a variety of ways including bulletin board systems (1978), Usenet (1980), Kermit (1981), and many others. The File Transfer Protocol (FTP) for use on the Internet was standardized in 1985 and is still in use today.A variety of tools were developed to aid the use of FTP by helping users discover files they might want to transfer, including the Wide Area Information Server (WAIS) in 1991, Gopher in 1991, Archie in 1991, Veronica in 1992, Jughead in 1993, Internet Relay Chat (IRC) in 1988, and eventually the World Wide Web (WWW) in 1991 with Web directories and Web search engines.
In 1999, Napster became the first peer-to-peer file sharing system.Napster used a central server for indexing and peer discovery, but the storage and transfer of files was decentralized. A variety of peer-to-peer file sharing programs and services with different levels of decentralization and anonymity followed, including: Gnutella, eDonkey2000, and Freenet in 2000, FastTrack, Kazaa, Limewire, and BitTorrent in 2001, and Poisoned in 2003.

All of these tools are general purpose and can be used to share a wide variety of content, but sharing of music files, software, and later movies and videos are major uses.And while some of this sharing is legal, large portions are not. Lawsuits and other legal actions caused Napster in 2001, eDonkey2000 in 2005, Kazza in 2006, and Limewire in 2010 to shutdown or refocus their efforts.

The Pirate Bay, founded in Sweden in 2003, continues despite a trial and appeal in 2009 and 2010 that resulted in jail terms and large fines for several of its founders. File sharing remains contentious and controversial with charges of theft of intellectual property on the one hand and charges of censorship on the other.

Dot-com bubble of internet

Dot-com bubble
Suddenly the low price of reaching millions worldwide, and the possibility of selling to or hearing from those people at the same moment when they were reached, promised to overturn established business dogma in advertising, mail-order sales, customer relationship management, and many more areas. The web was a new killer app—it could bring together unrelated buyers and sellers in seamless and low-cost ways. Entrepreneurs around the world developed new business models, and ran to their nearest venture capitalist. While some of the new entrepreneurs had experience in business and economics, the majority were simply people with ideas, and did not manage the capital influx prudently. Additionally, many dot-com business plans were predicated on the assumption that by using the Internet, they would bypass the distribution channels of existing businesses and therefore not have to compete with them; when the established businesses with strong existing brands developed their own Internet presence, these hopes were shattered, and the newcomers were left attempting to break into markets dominated by larger, more established businesses. Many did not have the ability to do so.
The dot-com bubble burst in March 2000, with the technology heavy NASDAQ Composite index peaking at 5,048.62 on March 10(5,132.52 intraday), more than double its value just a year before. By 2001, the bubble's deflation was running full speed. A majority of the dot-coms had ceased trading, after having burnt through their venture capital and IPO capital, often without ever making a profit. But despite this, the Internet continues to grow, driven by commerce, ever greater amounts of online information and knowledge and social networking.

Mobile Web

Mobile Web
The first mobile phone with Internet connectivity was the Nokia 9000 Communicator, launched in Finland in 1996. The viability of Internet services access on mobile phones was limited until prices came down from that model and network providers started to develop systems and services conveniently accessible on phones. NTT DoCoMo in Japan launched the first mobile Internet service, i-mode, in 1999 and this is considered the birth of the mobile phone Internet services. In 2001, the mobile phone email system by Research in Motion for their BlackBerry product was launched in America. To make efficient use of the small screen and tiny keypad and one-handed operation typical of mobile phones, a specific document and networking model was created for mobile devices, the Wireless Application Protocol (WAP). Most mobile device Internet services operate using WAP. The growth of mobile phone services was initially a primarily Asian phenomenon with Japan, South Korea and Taiwan all soon finding the majority of their Internet users accessing resources by phone rather than by PC.[citation needed] Developing countries followed, with India, South Africa, Kenya, Philippines, and Pakistan all reporting that the majority of their domestic users accessed the Internet from a mobile phone rather than a PC. The European and North American use of the Internet was influenced by a large installed base of personal computers, and the growth of mobile phone Internet access was more gradual, but had reached national penetration levels of 20–30% in most Western countries.The cross-over occurred in 2008, when more Internet access devices were mobile phones than personal computers. In many parts of the developing world, the ratio is as much as 10 mobile phone users to one PC user.

InterNIC, Internet Assigned Numbers Authority, and ICANN

InterNIC, Internet Assigned Numbers Authority, and ICANN
The IANA function was originally performed by USC Information Sciences Institute, and it delegated portions of this responsibility with respect to numeric network and autonomous system identifiers to the Network Information Center (NIC) at Stanford Research Institute (SRI International) in Menlo Park, California. In addition to his role as the RFC Editor, Jon Postel worked as the manager of IANA until his death in 1998.
As the early ARPANET grew, hosts were referred to by names, and a HOSTS.TXT file would be distributed from SRI International to each host on the network. As the network grew, this became cumbersome. A technical solution came in the form of the Domain Name System, created by Paul Mockapetris. The Defense Data Network—Network Information Center (DDN-NIC) at SRI handled all registration services, including the top-level domains (TLDs) of .mil, .gov, .edu, .org, .net, .com and .us, root nameserver administration and Internet number assignments under a United States Department of Defense contract.[56] In 1991, the Defense Information Systems Agency (DISA) awarded the administration and maintenance of DDN-NIC (managed by SRI up until this point) to Government Systems, Inc., who subcontracted it to the small private-sector Network Solutions, Inc.
The increasing cultural diversity of the Internet also posed administrative challenges for centralized management of the IP addresses. In October 1992, the Internet Engineering Task Force (IETF) published RFC 1366, which described the "growth of the Internet and its increasing globalization" and set out the basis for an evolution of the IP registry process, based on a regionally distributed registry model. This document stressed the need for a single Internet number registry to exist in each geographical region of the world (which would be of "continental dimensions"). Registries would be "unbiased and widely recognized by network providers and subscribers" within their region. The RIPE Network Coordination Centre (RIPE NCC) was established as the first RIR in May 1992. The second RIR, the Asia Pacific Network Information Centre (APNIC), was established in Tokyo in 1993, as a pilot project of the Asia Pacific Networking Group.
Since at this point in history most of the growth on the Internet was coming from non-military sources, it was decided that the Department of Defense would no longer fund registration services outside of the .mil TLD. In 1993 the U.S. National Science Foundation, after a competitive bidding process in 1992, created the InterNIC to manage the allocations of addresses and management of the address databases, and awarded the contract to three organizations. Registration Services would be provided by Network Solutions; Directory and Database Services would be provided by AT&T; and Information Services would be provided by General Atomics.
Over time, after consultation with the IANA, the IETF, RIPE NCC, APNIC, and the Federal Networking Council (FNC), the decision was made to separate the management of domain names from the management of IP numbers. Following the examples of RIPE NCC and APNIC, it was recommended that management of IP address space then administered by the InterNIC should be under the control of those that use it, specifically the ISPs, end-user organizations, corporate entities, universities, and individuals. As a result, the American Registry for Internet Numbers (ARIN) was established as in December 1997, as an independent, not-for-profit corporation by direction of the National Science Foundation and became the third Regional Internet Registry.
In 1998, both the IANA and remaining DNS-related InterNIC functions were reorganized under the control of ICANN, a California non-profit corporation contracted by the United States Department of Commerce to manage a number of Internet-related tasks. As these tasks involved technical coordination for two principal Internet name spaces (DNS names and IP addresses) created by the IETF, ICANN also signed a memorandum of understanding with the IAB to define the technical work to be carried out by the Internet Assigned Numbers Authority.The management of Internet address space remained with the regional Internet registries, which collectively were defined as a supporting organization within the ICANN structure.[64] ICANN provides central coordination for the DNS system, including policy coordination for the split registry / registrar system, with competition among registry service providers to serve each top-level-domain and multiple competing registrars offering DNS services to end-users.

The Internet Society

The Internet Society
The Internet Society or ISOC is an international, nonprofit organization founded during 1992 to "to assure the open development, evolution and use of the Internet for the benefit of all people throughout the world". With offices near Washington, DC, USA, and in Geneva, Switzerland, ISOC has a membership base comprising more than 80 organizational and more than 50,000 individual members. Members also form "chapters" based on either common geographical location or special interests. There are currently more than 90 chapters around the world.
ISOC provides financial and organizational support to and promotes the work of the standards settings bodies for which it is the organizational home: the Internet Engineering Task Force (IETF), the Internet Architecture Board (IAB), the Internet Engineering Steering Group (IESG), and the Internet Research Task Force (IRTF). ISOC also promotes understanding and appreciation of the Internet model of open, transparent processes and consensus-based decision making.

Globalization and Internet governance in the 21st century
Since the 1990s, the Internet's governance and organization has been of global importance to governments, commerce, civil society, and individuals. The organizations which held control of certain technical aspects of the Internet were the successors of the old ARPANET oversight and the current decision-makers in the day-to-day technical aspects of the network. While recognized as the administrators of certain aspects of the Internet, their roles and their decision making authority are limited and subject to increasing international scrutiny and increasing objections. These objections have led to the ICANN removing themselves from relationships with first the University of Southern California in 2000,and finally in September 2009, gaining autonomy from the US government by the ending of its longstanding agreements, although some contractual obligations with the U.S. Department of Commerce continued.

The IETF, with financial and organizational support from the Internet Society, continues to serve as the Internet's ad-hoc standards body and issues Request for Comments.
In November 2005, the World Summit on the Information Society, held in Tunis, called for an Internet Governance Forum (IGF) to be convened by United Nations Secretary General. The IGF opened an ongoing, non-binding conversation among stakeholders representing governments, the private sector, civil society, and the technical and academic communities about the future of Internet governance. The first IGF meeting was held in October/November 2006 with follow up meetings annually thereafter. Since WSIS, the term "Internet governance" has been broadened beyond narrow technical concerns to include a wider range of Internet-related policy issues.

Request for Comments in internet

Request for Comments
Request for Comments (RFCs) are the main documentation for the work of the IAB, IESG, IETF, and IRTF. RFC 1, "Host Software", was written by Steve Crocker at UCLA in April 1969, well before the IETF was created. Originally they were technical memos documenting aspects of ARPANET development and were edited by the late Jon Postel, the first RFC Editor.
RFCs cover a wide range of information from proposed standards, draft standards, full standards, best practices, experimental protocols, history, and other informational topics. RFCs can be written by individuals or informal groups of individuals, but many are the product of a more formal Working Group. Drafts are submitted to the IESG either by individuals or by the Working Group Chair. An RFC Editor, appointed by the IAB, separate from IANA, and working in conjunction with the IESG, receives drafts from the IESG and edits, formats, and publishes them. Once an RFC is published, it is never revised. If the standard it describes changes or its information becomes obsolete, the revised standard or updated information will be re-published as a new RFC that "obsoletes" the original.

Internet Engineering Task Force

Internet Engineering Task Force
The Internet Engineering Task Force (IETF) is the largest and most visible of several loosely related ad-hoc groups that provide technical direction for the Internet, including the Internet Architecture Board (IAB), the Internet Engineering Steering Group (IESG), and the Internet Research Task Force (IRTF).
The IETF is a loosely self-organized group of international volunteers who contribute to the engineering and evolution of Internet technologies. It is the principal body engaged in the development of new Internet standard specifications. Much of the IETF's work is done in Working Groups. It does not "run the Internet", despite what some people might mistakenly say. The IETF does make voluntary standards that are often adopted by Internet users, but it does not control, or even patrol, the Internet.
The IETF started in January 1986 as a quarterly meeting of U.S. government funded researchers. Non-government representatives were invited starting with the fourth IETF meeting in October 1986. The concept of Working Groups was introduced at the fifth IETF meeting in February 1987. The seventh IETF meeting in July 1987 was the first meeting with more than 100 attendees. In 1992, the Internet Society, a professional membership society, was formed and IETF began to operate under it as an independent international standards body. The first IETF meeting outside of the United States was held in Amsterdam, The Netherlands, in July 1993. Today the IETF meets three times a year and attendnce is often about 1,300 people, but has been as high as 2,000 upon occasion. Typically one in three IETF meetings are held in Europe or Asia. The number of non-US attendees is roughly 50%, even at meetings held in the United States.
The IETF is unusual in that it exists as a collection of happenings, but is not a corporation and has no board of directors, no members, and no dues. The closest thing there is to being an IETF member is being on the IETF or a Working Group mailing list. IETF volunteers come from all over the world and from many different parts of the Internet community. The IETF works closely with and under the supervision of the Internet Engineering Steering Group (IESG) and the Internet Architecture Board (IAB).[68] The Internet Research Task Force (IRTF) and the Internet Research Steering Group (IRSG), peer activities to the IETF and IESG under the general supervision of the IAB, focus on longer term research issues.

Intellectual property in internet

 Intellectual property

The intellectual property rights for any creative work initially rests with its creator. Web users who want to publish their work onto the World Wide Web, however, need to be aware of the details of the way they do it. If artwork, photographs, writings, poems, or technical innovations are published by their creator onto a privately owned web server, then they may choose the copyright and other conditions freely themselves. This is unusual though; more commonly work is uploaded to web sites and servers that are owned by other organizations. It depends upon the terms and conditions of the site or service provider to what extent the original owner automatically signs over rights to their work by the choice of destination and by the act of uploading.[citation needed]
Many users of the web erroneously assume that everything they may find on line is freely available to them as if it was in the public domain. This is almost never the case, unless the web site publishing the work clearly states that it is. On the other hand, content owners are aware of this widespread belief, and expect that sooner or later almost everything that is published will probably be used in some capacity somewhere without their permission. Many publishers therefore embed visible or invisible digital watermarks in their media files, sometimes charging users to receive unmarked copies for legitimate use. Digital rights management includes forms of access control technology that further limit the use of digital content even after it has been bought or downloaded.

Statistics in internet

Statistics

Between 2005 and 2010, the number of Web users doubled, and was expected to surpass two billion in 2010. Early studies in 1998 and 1999 estimating the size of the web using capture/recapture methods showed that much of the web was not indexed by search engines and the web was much larger than expected.
According to a 2001 study, there were a massive number, over 550 billion, of documents on the Web, mostly in the invisible Web, or Deep Web.
 A 2002 survey of 2,024 million Web pages determined that by far the most Web content was in the English language: 56.4%; next were pages in German (7.7%), French (5.6%), and Japanese (4.9%). A more recent study, which used Web searches in 75 different languages to sample the Web, determined that there were over 11.5 billion Web pages in the publicly indexable Web as of the end of January 2005.As of March 2009, the indexable web contains at least 25.21 billion pages.

On 25 July 2008, Google software engineers Jesse Alpert and Nissan Hajaj announced that Google Search had discovered one trillion unique URLs.[63] As of May 2009, over 109.5 million domains operated.[64][not in citation given] Of these 74% were commercial or other sites operating in the .com generic top-level domain.
Statistics measuring a website's popularity are usually based either on the number of page views or on associated server 'hits' (file requests) that it receives.

Web accessibility

Web accessibility
There are methods available for accessing the web in alternative mediums and formats, so as to enable use by individuals with disabilities. These disabilities may be visual, auditory, physical, speech related, cognitive, neurological, or some combination therin. Accessibility features also help others with temporary disabilities like a broken arm or the aging population as their abilities change.The Web is used for receiving information as well as providing information and interacting with society. The World Wide Web Consortium claims it essential that the Web be accessible in order to provide equal access and equal opportunity to people with disabilities.
Tim Berners-Lee once noted, "The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect." Many countries regulate web accessibility as a requirement for websites.
 International cooperation in the W3C Web Accessibility Initiative led to simple guidelines that web content authors as well as software developers can use to make the Web accessible to persons who may or may not be using assistive technology.

Web standards

Web standards
Many formal standards and other technical specifications and software define the operation of different aspects of the World Wide Web, the Internet, and computer information exchange. Many of the documents are the work of the World Wide Web Consortium (W3C), headed by Berners-Lee, but some are produced by the Internet Engineering Task Force (IETF) and other organizations.
Usually, when web standards are discussed, the following publications are seen as foundational:
Recommendations for markup languages, especially HTML and XHTML, from the W3C. These define the structure and interpretation of hypertext documents.
Recommendations for stylesheets, especially CSS, from the W3C.
Standards for ECMAScript (usually in the form of JavaScript), from Ecma International.
Recommendations for the Document Object Model, from W3C.
Additional publications provide definitions of other essential technologies for the World Wide Web, including, but not limited to, the following:
Uniform Resource Identifier (URI), which is a universal system for referencing resources on the Internet, such as hypertext documents and images. URIs, often called URLs, are defined by the IETF's RFC 3986 / STD 66: Uniform Resource Identifier (URI): Generic Syntax, as well as its predecessors and numerous URI scheme-defining RFCs;
HyperText Transfer Protocol (HTTP), especially as defined by RFC 2616: HTTP/1.1 and RFC 2617: HTTP Authentication, which specify how the browser and server authenticate each other.

Security of internet

Security of internet

The Web has become criminals' preferred pathway for spreading malware. Cybercrime carried out on the Web can include identity theft, fraud, espionage and intelligence gathering.Web-based vulnerabilities now outnumber traditional computer security concerns, and as measured by Google, about one in ten web pages may contain malicious code.Most Web-based attacks take place on legitimate websites, and most, as measured by Sophos, are hosted in the United States, China and Russia.The most common of all malware threats is SQL injection attacks against websites. Through HTML and URIs the Web was vulnerable to attacks like cross-site scripting (XSS) that came with the introduction of JavaScript and were exacerbated to some degree by Web 2.0 and Ajax web design that favors the use of scripts.Today by one estimate, 70% of all websites are open to XSS attacks on their users.
Proposed solutions vary to extremes. Large security vendors like McAfee already design governance and compliance suites to meet post-9/11 regulations, and some, like Finjan have recommended active real-time inspection of code and all content regardless of its source.Some have argued that for enterprise to see security as a business opportunity rather than a cost center, "ubiquitous, always-on digital rights management" enforced in the infrastructure by a handful of organizations must replace the hundreds of companies that today secure data and networks. Jonathan Zittrain has said users sharing responsibility for computing safety is far preferable to locking down the Internet.

Web cache

 Web cache
If a user revisits a Web page after only a short interval, the page data may not need to be re-obtained from the source Web server. Almost all web browsers cache recently obtained data, usually on the local hard drive. HTTP requests sent by a browser will usually ask only for data that has changed since the last download. If the locally cached data are still current, they will be reused. Caching helps reduce the amount of Web traffic on the Internet. The decision about expiration is made independently for each downloaded file, whether image, stylesheet, JavaScript, HTML, or other web resource. Thus even on sites with highly dynamic content, many of the basic resources need to be refreshed only occasionally. Web site designers find it worthwhile to collate resources such as CSS data and JavaScript into a few site-wide files so that they can be cached efficiently. This helps reduce page download times and lowers demands on the Web server.
There are other components of the Internet that can cache Web content. Corporate and academic firewalls often cache Web resources requested by one user for the benefit of all. (See also caching proxy server.) Some search engines also store cached content from websites. Apart from the facilities built into Web servers that can determine when files have been updated and so need to be re-sent, designers of dynamically generated Web pages can control the HTTP headers sent back to requesting users, so that transient or sensitive pages are not cached. Internet banking and news sites frequently use this facility. Data requested with an HTTP 'GET' is likely to be cached if other conditions are met; data obtained in response to a 'POST' is assumed to depend on the data that was POSTed and so is not cached.

Internet privacy

Internet privacy
Every time a web page is requested from a web server the server can identify, and usually it logs, the IP address from which the request arrived. Equally, unless set not to do so, most web browsers record the web pages that have been requested and viewed in a history feature, and usually cache much of the content locally. Unless HTTPS encryption is used, web requests and responses travel in plain text across the internet and they can be viewed, recorded and cached by intermediate systems.
When a web page asks for, and the user supplies, personally identifiable information such as their real name, address, e-mail address, etc., then a connection can be made between the current web traffic and that individual. If the website uses HTTP cookies, username and password authentication, or other tracking techniques, then it will be able to relate other web visits, before and after, to the identifiable information provided. In this way it is possible for a web-based organisation to develop and build a profile of the individual people who use its site or sites. It may be able to build a record for an individual that includes information about their leisure activities, their shopping interests, their profession, and other aspects of their demographic profile. These profiles are obviously of potential interest to marketeers, advertisers and others. Depending on the website's terms and conditions and the local laws that apply information from these profiles may be sold, shared, or passed to other organisations without the user being informed. For many ordinary people, this means little more than some unexpected e-mails in their in-box, or some uncannily relevant advertising on a future web page. For others, it can mean that time spent indulging an unusual interest can result in a deluge of further targeted marketing that may be unwelcome. Law enforcement, counter terrorism and espionage agencies can also identify, target and track individuals based on what appear to be their interests or proclivities on the web.
Social networking sites make a point of trying to get the user to truthfully expose their real names, interests and locations. This makes the social networking experience more realistic and therefore engaging for all their users. On the other hand, photographs uploaded and unguarded statements made will be identified to the individual, who may regret some decisions to publish these data. Employers, schools, parents and other relatives may be influenced by aspects of social networking profiles that the posting individual did not intend for these audiences. On-line bullies may make use of personal information to harass or stalk users. Modern social networking websites allow fine grained control of the privacy settings for each individual posting, but these can be complex and not easy to find or use, especially for beginners.
Photographs and videos posted onto websites have caused particular problems, as they can add a person's face to an on-line profile. With modern and potential facial recognition technology, it may then be possible to relate that face with other, previously anonymous, images, events and scenarios that have been imaged elsewhere. Because of image caching, mirroring and copying, it is difficult to remove an image from the World Wide Web.

WWW prefix

WWW prefix
Many domain names used for the World Wide Web begin with www because of the long-standing practice of naming Internet hosts (servers) according to the services they provide. The hostname for a web server is often www, in the same way that it may be ftp for an FTP server, and news or nntp for a USENET news server. These host names appear as Domain Name System or [domain name server](DNS) subdomain names, as in www.example.com. The use of 'www' as a subdomain name is not required by any technical or policy standard and many web sites do not use it; indeed, the first ever web server was called nxoc01.cern.ch.[28] According to Paolo Palazzi,[29] who worked at CERN along with Tim Berners-Lee, the popular use of 'www' subdomain was accidental; the World Wide Web project page was intended to be published at www.cern.ch while info.cern.ch was intended to be the CERN home page, however the dns records were never switched, and the practice of prepending 'www' to an institution's website domain name was subsequently copied. Many established websites still use 'www', or they invent other subdomain names such as 'www2', 'secure', etc. Many such web servers are set up so that both the domain root (e.g., example.com) and the www subdomain (e.g., www.example.com) refer to the same site; others require one form or the other, or they may map to different web sites.
The use of a subdomain name is useful for load balancing incoming web traffic by creating a CNAME record that points to a cluster of web servers. Since, currently, only a subdomain can be used in a CNAME, the same result cannot be achieved by using the bare domain root.
When a user submits an incomplete domain name to a web browser in its address bar input field, some web browsers automatically try adding the prefix "www" to the beginning of it and possibly ".com", ".org" and ".net" at the end, depending on what might be missing. For example, entering 'microsoft' may be transformed to http://www.microsoft.com/ and 'openoffice' to http://www.openoffice.org. This feature started appearing in early versions of Mozilla Firefox, when it still had the working title 'Firebird' in early 2003, from an earlier practice in browsers such as Lynx. It is reported that Microsoft was granted a US patent for the same idea in 2008, but only for mobile devices.

In English, www is usually read as double-u double-u double-u. Some users pronounce it dub-dub-dub, particularly in New Zealand. Stephen Fry, in his "Podgrammes" series of podcasts, pronouncing it wuh wuh wuh. The English writer Douglas Adams once quipped in The Independent on Sunday (1999): "The World Wide Web is the only thing I know of whose shortened form takes three times longer to say than what it's short for". In Mandarin Chinese, World Wide Web is commonly translated via a phono-semantic matching to wàn wéi wǎng (万维网), which satisfies www and literally means "myriad dimensional net", a translation that very appropriately reflects the design concept and proliferation of the World Wide Web. Tim Berners-Lee's web-space states that World Wide Web is officially spelled as three separate words, each capitalised, with no intervening hyphens.
Use of the www prefix is declining as Web 2.0 web applications seek to brand their domain names and make them easily pronounceable. As the mobile web grows in popularity, services like Gmail.com, MySpace.com, Facebook.com, Bebo.com and Twitter.com are most often discussed without adding www to the domain (or, indeed, the .com).

Dynamic updates of web pages

JavaScript is a scripting language that was initially developed in 1995 by Brendan Eich, then of Netscape, for use within web pages. The standardised version is ECMAScript.To make web pages more interactive, some web applications also use JavaScript techniques such as Ajax (asynchronous JavaScript and XML). Client-side script is delivered with the page that can make additional HTTP requests to the server, either in response to user actions such as mouse movements or clicks, or based on lapsed time. The server's responses are used to modify the current page rather than creating a new page with each response, so the server needs only to provide limited, incremental information. Multiple Ajax requests can be handled at the same time, and users can interact with the page while data is being retrieved. Web pages may also regularly poll the server to check whether new information is available.

Linking in internet of WWW

Linking in internet of WWW
Most web pages contain hyperlinks to other related pages and perhaps to downloadable files, source documents, definitions and other web resources. In the underlying HTML, a hyperlink looks like
<a href="http://example.org/wiki/Main_Page">Example.org, a free encyclopedia</a>


Graphic representation of a minute fraction of the WWW, demonstrating hyperlinks
Such a collection of useful, related resources, interconnected via hypertext links is dubbed a web of information. Publication on the Internet created what Tim Berners-Lee first called the WorldWideWeb (in its original CamelCase, which was subsequently discarded) in November 1990.


The hyperlink structure of the WWW is described by the webgraph: the nodes of the webgraph correspond to the web pages (or URLs) the directed edges between them to the hyperlinks.
Over time, many web resources pointed to by hyperlinks disappear, relocate, or are replaced with different content. This makes hyperlinks obsolete, a phenomenon referred to in some circles as link rot and the hyperlinks affected by it are often called dead links. The ephemeral nature of the Web has prompted many efforts to archive web sites. The Internet Archive, active since 1996, is the best known of such efforts.

Function of terms Internet and World Wide Web

The terms Internet and World Wide Web are often used in everyday speech without much distinction. However, the Internet and the World Wide Web are not the same. The Internet is a global system of interconnected computer networks. In contrast, the Web is one of the services that runs on the Internet. It is a collection of text documents and other resources, linked by hyperlinks and URLs, usually accessed by web browsers from web servers. In short, the Web can be thought of as an application "running" on the Internet.
Viewing a web page on the World Wide Web normally begins either by typing the URL of the page into a web browser or by following a hyperlink to that page or resource. The web browser then initiates a series of communication messages, behind the scenes, in order to fetch and display it. As an example, consider accessing a page with the URL http://example.org/wiki/World_Wide_Web.
First, the browser resolves the server-name portion of the URL (example.org) into an Internet Protocol address using the globally distributed database known as the Domain Name System (DNS); this lookup returns an IP address such as 208.80.152.2. The browser then requests the resource by sending an HTTP request across the Internet to the computer at that particular address. It makes the request to a particular application port in the underlying Internet Protocol Suite so that the computer receiving the request can distinguish an HTTP request from other network protocols it may be servicing such as e-mail delivery; the HTTP protocol normally uses port 80. The content of the HTTP request can be as simple as the two lines of text
GET /wiki/World_Wide_Web HTTP/1.1
Host: example.org
The computer receiving the HTTP request delivers it to web server software listening for requests on port 80. If the web server can fulfill the request it sends an HTTP response back to the browser indicating success, which can be as simple as
HTTP/1.0 200 OK
Content-Type: text/html; charset=UTF-8
followed by the content of the requested page. The Hypertext Markup Language for a basic web page looks like


<html>
<head>
<title>Example.org – The World Wide Web</title>
</head>
<body>
<p>The World Wide Web, abbreviated as WWW and commonly known ...</p>
</body>
</html>


The web browser parses the HTML, interpreting the markup (<title>, <p> for paragraph, and such) that surrounds the words in order to draw the text on the screen.
Many web pages use HTML to reference the URLs of other resources such as images, other embedded media, scripts that affect page behavior, and Cascading Style Sheets that affect page layout. The browser will make additional HTTP requests to the web server for these other Internet media types. As it receives their content from the web server, the browser progressively renders the page onto the screen as specified by its HTML and these additional resources.

The World Wide Web (abbreviated as WWW or W3

The World Wide Web (abbreviated as WWW or W3, commonly known as the Web), is a system of interlinked hypertext documents accessed via the Internet. With a web browser, one can view web pages that may contain text, images, videos, and other multimedia, and navigate between them via hyperlinks.
Using concepts from his earlier hypertext systems like ENQUIRE, British engineer, computer scientist and at that time employee of CERN, Sir Tim Berners-Lee, now Director of the World Wide Web Consortium (W3C), wrote a proposal in March 1989 for what would eventually become the World Wide Web. At CERN, a European research organisation near Geneva situated on Swiss and French soil, Berners-Lee and Belgian computer scientist Robert Cailliau proposed in 1990 to use hypertext "to link and access information of various kinds as a web of nodes in which the user can browse at will",and they publicly introduced the project in December of the same year.

History of the World Wide Web

 History of the World Wide Web


The NeXT Computer used by Berners-Lee. The handwritten label declares, "This machine is a server. DO NOT POWER IT DOWN!!"
In the May 1970 issue of Popular Science magazine, Arthur C. Clarke predicted that satellites would someday "bring the accumulated knowledge of the world to your fingertips" using a console that would combine the functionality of the photocopier, telephone, television and a small computer, allowing data transfer and video conferencing around the globe.
In March 1989, Tim Berners-Lee wrote a proposal that referenced ENQUIRE, a database and software project he had built in 1980, and described a more elaborate information management system.
With help from Robert Cailliau, he published a more formal proposal (on 12 November 1990) to build a "Hypertext project" called "WorldWideWeb" (one word, also "W3") as a "web" of "hypertext documents" to be viewed by "browsers" using a client–server architecture. This proposal estimated that a read-only web would be developed within three months and that it would take six months to achieve "the creation of new links and new material by readers, [so that] authorship becomes universal" as well as "the automatic notification of a reader when new material of interest to him/her has become available." While the read-only goal was met, accessible authorship of web content took longer to mature, with the wiki concept, blogs, Web 2.0 and RSS/Atom.
The proposal was modeled after the Dynatext SGML reader by Electronic Book Technology, a spin-off from the Institute for Research in Information and Scholarship at Brown University. The Dynatext system, licensed by CERN, was technically advanced and was a key player in the extension of SGML ISO 8879:1986 to Hypermedia within HyTime, but it was considered too expensive and had an inappropriate licensing policy for use in the general high energy physics community, namely a fee for each document and each document alteration.

The CERN of WWW servers

The CERN datacenter in 2010 housing some WWW servers
A NeXT Computer was used by Berners-Lee as the world's first web server and also to write the first web browser, WorldWideWeb, in 1990. By Christmas 1990, Berners-Lee had built all the tools necessary for a working Web:the first web browser (which was a web editor as well); the first web server; and the first web pages, which described the project itself. On 6 August 1991, he posted a short summary of the World Wide Web project on the alt.hypertext newsgroup.This date also marked the debut of the Web as a publicly available service on the Internet. Many newsmedia have reported that the first photo on the web was uploaded by Berners-Lee in 1992, an image of the CERN house band Les Horribles Cernettes taken by Silvano de Gennaro; Gennaro has disclaimed this story, writing that media were "totally distorting our words for the sake of cheap sensationalism."The first server outside Europe was set up at the Stanford Linear Accelerator Center (SLAC) in Palo Alto, California, to host the SPIRES-HEP database. Accounts differ substantially as to the date of this event. The World Wide Web Consortium says December 1992, whereas SLAC itself claims 1991.This is supported by a W3C document titled A Little History of the World Wide Web.
The crucial underlying concept of hypertext originated with older projects from the 1960s, such as the Hypertext Editing System (HES) at Brown University, Ted Nelson's Project Xanadu, and Douglas Engelbart's oN-Line System (NLS). Both Nelson and Engelbart were in turn inspired by Vannevar Bush's microfilm-based "memex", which was described in the 1945 essay "As We May Think".
Berners-Lee's breakthrough was to marry hypertext to the Internet. In his book Weaving The Web, he explains that he had repeatedly suggested that a marriage between the two technologies was possible to members of both technical communities, but when no one took up his invitation, he finally tackled the project himself. In the process, he developed three essential technologies:
a system of globally unique identifiers for resources on the Web and elsewhere, the universal document identifier (UDI), later known as uniform resource locator (URL) and uniform resource identifier (URI);
the publishing language HyperText Markup Language (HTML);
the Hypertext Transfer Protocol (HTTP).
The World Wide Web had a number of differences from other hypertext systems that were then available. The Web required only unidirectional links rather than bidirectional ones. This made it possible for someone to link to another resource without action by the owner of that resource. It also significantly reduced the difficulty of implementing web servers and browsers (in comparison to earlier systems), but in turn presented the chronic problem of link rot. Unlike predecessors such as HyperCard, the World Wide Web was non-proprietary, making it possible to develop servers and clients independently and to add extensions without licensing restrictions. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone, with no fees due. Coming two months after the announcement that the server implementation of the Gopher protocol was no longer free to use, this produced a rapid shift away from Gopher and towards the Web. An early popular web browser was ViolaWWW for Unix and the X Windowing System.


Robert Cailliau, Jean-François Abramatic of IBM, and Tim Berners-Lee at the 10th anniversary of the World Wide Web Consortium.
Scholars generally agree that a turning point for the World Wide Web began with the introduction of the Mosaic web browser in 1993, a graphical browser developed by a team at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign (NCSA-UIUC), led by Marc Andreessen. Funding for Mosaic came from the U.S. High-Performance Computing and Communications Initiative and the High Performance Computing and Communication Act of 1991, one of several computing developments initiated by U.S. Senator Al Gore. Prior to the release of Mosaic, graphics were not commonly mixed with text in web pages and the Web's popularity was less than older protocols in use over the Internet, such as Gopher and Wide Area Information Servers (WAIS). Mosaic's graphical user interface allowed the Web to become, by far, the most popular Internet protocol.
The World Wide Web Consortium (W3C) was founded by Tim Berners-Lee after he left the European Organization for Nuclear Research (CERN) in October 1994. It was founded at the Massachusetts Institute of Technology Laboratory for Computer Science (MIT/LCS) with support from the Defense Advanced Research Projects Agency (DARPA), which had pioneered the Internet; a year later, a second site was founded at INRIA (a French national computer research lab) with support from the European Commission DG InfSo; and in 1996, a third continental site was created in Japan at Keio University. By the end of 1994, while the total number of websites was still minute compared to present standards, quite a number of notable websites were already active, many of which are the precursors or inspiration for today's most popular services.
Connected by the existing Internet, other websites were created around the world, adding international standards for domain names and HTML. Since then, Berners-Lee has played an active role in guiding the development of web standards (such as the markup languages in which web pages are composed), and in recent years has advocated his vision of a Semantic Web. The World Wide Web enabled the spread of information over the Internet through an easy-to-use and flexible format. It thus played an important role in popularizing use of the Internet.Although the two terms are sometimes conflated in popular use, World Wide Web is not synonymous with Internet.
The Web is a collection of documents and both client and server software using Internet protocols such as TCP/IP and HTTP. Tim Berners-Lee was knighted in 2004 by Queen Elizabeth II for his contribution to the World Wide Web.

Telecommuting In Internet

Telecommuting
Remote work is facilitated by tools such as groupware, virtual private networks, conference calling, videoconferencing, and Voice over IP (VOIP). It can be efficient and useful for companies as it allows workers to communicate over long distances, saving significant amounts of travel time and cost. As broadband Internet connections become more commonplace, more and more workers have adequate bandwidth at home to use these tools to link their home to their corporate intranet and internal phone networks.


Telecommuters' tendency to shop online while still on the clock could be eating into their budgets –– and, possibly, their work performance, according to a new survey by Coupon Cabin.
Nearly 70 percent of people who work from home said they have been known to browse the virtual shopping aisles of the Internet while working. That is compared to about half of some 2,000 respondents who admitted to online shopping while in the office.
One-quarter of workers aid they spend about an hour per week shopping online, nearly double the number of people who shop online while at the office.
Without prying eyes skimming over their computer screen whenever they pass by, there is no real threat stopping people from casually picking up a new pair of boots during a conference call. Half of telecommuting shoppers said they do it because they feel they're less likely to get caught, plain and simple.
In the grand scheme of the telecommuting debate, this study may seem like more fuel for the opposition. But telecommuters still say they are less distracted and feel more efficient when working from a home office than in a cubicle.
However, there is still a case to be made for telecommuting's negative impact on bank accounts. Most career experts recommend employees takes breaks at home just as they would in any regular office, but scheduling a walk or a little at-home yoga may be a healthier use of that time than burning a hole through your credit card.

Transition towards the Internet

Transition towards the Internet
The term "internet" was adopted in the first RFC published on the TCP protocol (RFC 675:Internet Transmission Control Program, December 1974) as an abbreviation of the term internetworking and the two terms were used interchangeably. In general, an internet was any network using TCP/IP. It was around the time when ARPANET was interlinked with NSFNET in the late 1980s, that the term was used as the name of the network, Internet,being the large and global TCP/IP network.
As interest in widespread networking grew and new applications for it were developed, the Internet's technologies spread throughout the rest of the world. The network-agnostic approach in TCP/IP meant that it was easy to use any existing network infrastructure, such as the IPSS X.25 network, to carry Internet traffic. In 1984, University College London replaced its transatlantic satellite links with TCP/IP over IPSS.
Many sites unable to link directly to the Internet started to create simple gateways to allow transfer of email, at that time the most important application. Sites which only had intermittent connections used UUCP or FidoNet and relied on the gateways between these networks and the Internet. Some gateway services went beyond simple email peering, such as allowing access to FTP sites via UUCP or email.
Finally, the Internet's remaining centralized routing aspects were removed. The EGP routing protocol was replaced by a new protocol, the Border Gateway Protocol (BGP). This turned the Internet into a meshed topology and moved away from the centric architecture which ARPANET had emphasized. In 1994, Classless Inter-Domain Routing was introduced to support better conservation of address space which allowed use of route aggregation to decrease the size of routing tables.

Packet switching in internet

Packet switching in internet


Len Kleinrock and the first Interface Message Processor.
At the tip of the problem lay the issue of connecting separate physical networks to form one logical network. During the 1960s, Paul Baran (RAND Corporation) produced a study of survivable networks for the US military. Information transmitted across Baran's network would be divided into what he called 'message-blocks'. Independently, Donald Davies (National Physical Laboratory, UK), proposed and developed a similar network based on what he called packet-switching, the term that would ultimately be adopted. Leonard Kleinrock (MIT) developed a mathematical theory behind this technology. Packet-switching provides better bandwidth utilization and response times than the traditional circuit-switching technology used for telephony, particularly on resource-limited interconnection links.
Packet switching is a rapid store-and-forward networking design that divides messages up into arbitrary packets, with routing decisions made per-packet. Early networks used message switched systems that required rigid routing structures prone to single point of failure. This led Tommy Krash and Paul Baran's U.S. military funded research to focus on using message-blocks to include network redundancy.
The widespread urban legend that the Internet was designed to resist a nuclear attack likely arose as a result of Baran's earlier work on packet switching, which did focus on redundancy in the face of a nuclear "holocaust."

RAND Corporation and ARPANET

RAND Corporation and ARPANET
A fundamental pioneer in the call for a global network, J. C. R. Licklider, articulated the ideas in his January 1960 paper, Man-Computer Symbiosis.
"A network of such [computers], connected to one another by wide-band communication lines [which provided] the functions of present-day libraries together with anticipated advances in information storage and retrieval and [other] symbiotic functions."
—J.C.R. Licklider,
In August 1962, Licklider and Welden Clark published the paper "On-Line Man Computer Communication", which was one of the first descriptions of a networked future.
In October 1962, Licklider was hired by Jack Ruina as Director of the newly established Information Processing Techniques Office (IPTO) within DARPA, with a mandate to interconnect the United States Department of Defense's main computers at Cheyenne Mountain, the Pentagon, and SAC HQ. There he formed an informal group within DARPA to further computer research. He began by writing memos describing a distributed network to the IPTO staff, whom he called "Members and Affiliates of the Intergalactic Computer Network". As part of the information processing office's role, three network terminals had been installed: one for System Development Corporation in Santa Monica, one for Project Genie at the University of California, Berkeley and one for the Compatible Time-Sharing System project at the Massachusetts Institute of Technology (MIT). Licklider's identified need for inter-networking would be made obvious by the apparent waste of resources this caused.
"For each of these three terminals, I had three different sets of user commands. So if I was talking online with someone at S.D.C. and I wanted to talk to someone I knew at Berkeley or M.I.T. about this, I had to get up from the S.D.C. terminal, go over and log into the other terminal and get in touch with them. [...] I said, it's obvious what to do (But I don't want to do it): If you have these three terminals, there ought to be one terminal that goes anywhere you want to go where you have interactive computing. That idea is the ARPAnet."
—Robert W. Taylor, co-writer with Licklider of "The Computer as a Communications Device", in an interview with The New York Times,
Although he left the IPTO in 1964, five years before the ARPANET went live, it was his vision of universal networking that provided the impetus that led his successors such as Lawrence Roberts and Robert Taylor to further the ARPANET development. Licklider later returned to lead the IPTO in 1973 for two years.

Victorian Internet

Victorian Internet
The telegraph system is the first fully digital communication system. Thus the Internet has precursors, such as the telegraph system, that date back to the 19th century, more than a century before the digital Internet became widely used in the second half of the 1990s. The concept of data communication – transmitting data between two different places, connected via some kind of electromagnetic medium, such as radio or an electrical wire – predates the introduction of the first computers. Such communication systems were typically limited to point to point communication between two end devices. Telegraph systems and telex machines can be considered early precursors of this kind of communication.
Fundamental theoretical work in data transmission and information theory was developed by Claude Shannon, Harry Nyquist, and Ralph Hartley, during the early 20th century.
Early computers used the technology available at the time to allow communication between the central processing unit and remote terminals. As the technology evolved, new systems were devised to allow communication over longer distances (for terminals) or with higher speed (for interconnection of local devices) that were necessary for the mainframe computer model. Using these technologies made it possible to exchange data (such as files) between remote computers. However, the point to point communication model was limited, as it did not allow for direct communication between any two arbitrary systems; a physical link was necessary. The technology was also deemed as inherently unsafe for strategic and military use, because there were no alternative paths for the communication in case of an enemy attack.

Crowdsourcing In Internet

Crowdsourcing In Internet
Internet provides a particularly good venue for crowdsourcing (outsourcing tasks to a distributed group of people) since individuals tend to be more open in web-based projects where they are not being physically judged or scrutinized and thus can feel more comfortable sharing.
Crowdsourcing systems are used to accomplish a variety of tasks. For example, the crowd may be invited to develop a new technology, carry out a design task, refine or carry out the steps of an algorithm (see human-based computation), or help capture, systematize, or analyze large amounts of data (see also citizen science).
Wikis have also been used in the academic community for sharing and dissemination of information across institutional and international boundaries. In those settings, they have been found useful for collaboration on grant writing, strategic planning, departmental documentation, and committee work. The United States Patent and Trademark Office uses a wiki to allow the public to collaborate on finding prior art relevant to examination of pending patent applications. Queens, New York has used a wiki to allow citizens to collaborate on the design and planning of a local park.
The English Wikipedia has the largest user base among wikis on the World Wide Web and ranks in the top 10 among all Web sites in terms of traffic.

Philanthropy In Internet

Philanthropy  In Internet
The spread of low-cost internet access in developing countries has opened up new possibilities for peer-to-peer charities, which allow individuals to contribute small amounts to charitable projects for other individuals. Websites, such as DonorsChoose and GlobalGiving, allow small-scale donors to direct funds to individual projects of their choice.
A popular twist on internet-based philanthropy is the use of peer-to-peer lending for charitable purposes. Kiva pioneered this concept in 2005, offering the first web-based service to publish individual loan profiles for funding. Kiva raises funds for local intermediary microfinance organizations which post stories and updates on behalf of the borrowers. Lenders can contribute as little as $25 to loans of their choice, and receive their money back as borrowers repay. Kiva falls short of being a pure peer-to-peer charity, in that loans are disbursed before being funded by lenders and borrowers do not communicate with lenders themselves.

However, the recent spread of low cost Internet access in developing countries has made genuine international person-to-person philanthropy increasingly feasible. In 2009 the US-based nonprofit Zidisha tapped into this trend to offer the first person-to-person microfinance platform to link lenders and borrowers across international borders without intermediaries. Members can fund loans for as little as a dollar, which the borrowers then use to develop business activities that improve their families' incomes while repaying loans to the members with interest. Borrowers access the internet via public cybercafes, donated laptops in village schools, and even smart phones, then create their own profile pages through which they share photos and information about themselves and their businesses. As they repay their loans, borrowers continue to share updates and dialogue with lenders via their profile pages. This direct web-based connection allows members themselves to take on many of the communication and recording tasks traditionally performed by local organizations, bypassing geographic barriers and dramatically reducing the cost of microfinance services to the entrepreneurs.

Politics and political revolutions In Internet

Politics and political revolutions  In Internet
The Internet has achieved new relevance as a political tool. The presidential campaign of Howard Dean in 2004 in the United States was notable for its success in soliciting donation via the Internet. Many political groups use the Internet to achieve a new method of organizing in order to carry out their mission, having given rise to Internet activism, most notably practiced by rebels in the Arab Spring.

The New York Times suggested that social media websites, such as Facebook and Twitter, helped people organize the political revolutions in Egypt where it helped certain classes of protesters organize protests, communicate grievances, and disseminate information.
The potential of the Internet as a civic tool of communicative power was thoroughly explored by Simon R. B. Berdal in his thesis of 2004:
As the globally evolving Internet provides ever new access points to virtual discourse forums, it also promotes new civic relations and associations within which communicative power may flow and accumulate. Thus, traditionally ... national-embedded peripheries get entangled into greater, international peripheries, with stronger combined powers... The Internet, as a consequence, changes the topology of the "centre-periphery" model, by stimulating conventional peripheries to interlink into "super-periphery" structures, which enclose and "besiege" several centres at once.
Berdal, therefore, extends the Habermasian notion of the Public sphere to the Internet, and underlines the inherent global and civic nature that intervowen Internet technologies provide. To limit the growing civic potential of the Internet, Berdal also notes how "self-protective measures" are put in place by those threatened by it:
If we consider China’s attempts to filter "unsuitable material" from the Internet, most of us would agree that this resembles a self-protective measure by the system against the growing civic potentials of the Internet. Nevertheless, both types represent limitations to "peripheral capacities". Thus, the Chinese government tries to prevent communicative power to build up and unleash (as the 1989 Tiananmen Square uprising suggests, the government may find it wise to install "upstream measures"). Even though limited, the Internet is proving to be an empowering tool also to the Chinese periphery: Analysts believe that Internet petitions have influenced policy implementation in favour of the public’s online-articulated will ..

Internet censorship and Internet freedom

Censorship  In Internet

Some governments, such as those of Burma, Iran, North Korea, the Mainland China, Saudi Arabia, and the United Arab Emirates restrict what people in their countries can access on the Internet, especially political and religious content. This is accomplished through software that filters domains and content so that they may not be easily accessed or obtained without elaborate circumvention.
In Norway, Denmark, Finland, and Sweden, major Internet service providers have voluntarily, possibly to avoid such an arrangement being turned into law, agreed to restrict access to sites listed by authorities. While this list of forbidden URLs is supposed to contain addresses of only known child pornography sites, the content of the list is secret. Many countries, including the United States, have enacted laws against the possession or distribution of certain material, such as child pornography, via the Internet, but do not mandate filtering software. There are many free and commercially available software programs, called content-control software, with which a user can choose to block offensive websites on individual computers or networks, in order to limit a child's access to pornographic materials or depiction of violence.

Politics and political revolutions
The Internet has achieved new relevance as a political tool. The presidential campaign of Howard Dean in 2004 in the United States was notable for its success in soliciting donation via the Internet. Many political groups use the Internet to achieve a new method of organizing in order to carry out their mission, having given rise to Internet activism, most notably practiced by rebels in the Arab Spring.[76][77]
The New York Times suggested that social media websites, such as Facebook and Twitter, helped people organize the political revolutions in Egypt where it helped certain classes of protesters organize protests, communicate grievances, and disseminate information.[78]
The potential of the Internet as a civic tool of communicative power was thoroughly explored by Simon R. B. Berdal in his thesis of 2004:
As the globally evolving Internet provides ever new access points to virtual discourse forums, it also promotes new civic relations and associations within which communicative power may flow and accumulate. Thus, traditionally ... national-embedded peripheries get entangled into greater, international peripheries, with stronger combined powers... The Internet, as a consequence, changes the topology of the "centre-periphery" model, by stimulating conventional peripheries to interlink into "super-periphery" structures, which enclose and "besiege" several centres at once.[79]
Berdal, therefore, extends the Habermasian notion of the Public sphere to the Internet, and underlines the inherent global and civic nature that intervowen Internet technologies provide. To limit the growing civic potential of the Internet, Berdal also notes how "self-protective measures" are put in place by those threatened by it:
If we consider China’s attempts to filter "unsuitable material" from the Internet, most of us would agree that this resembles a self-protective measure by the system against the growing civic potentials of the Internet. Nevertheless, both types represent limitations to "peripheral capacities". Thus, the Chinese government tries to prevent communicative power to build up and unleash (as the 1989 Tiananmen Square uprising suggests, the government may find it wise to install "upstream measures"). Even though limited, the Internet is proving to be an empowering tool also to the Chinese periphery: Analysts believe that Internet petitions have influenced policy implementation in favour of the public’s online-articulated will ..

Internet is Electronic Business

 Electronic business
Electronic business (E-business) involves business processes spanning the entire value chain: electronic purchasing and supply chain management, processing orders electronically, handling customer service, and cooperating with business partners. E-commerce seeks to add revenue streams using the Internet to build and enhance relationships with clients and partners.
According to research firm IDC, the size of total worldwide e-commerce, when global business-to-business and -consumer transactions are added together, will equate to $16 trillion in 2013. IDate, another research firm, estimates the global market for digital products and services at $4.4 trillion in 2013. A report by Oxford Economics adds those two together to estimate the total size of the digital economy at $20.4 trillion, equivalent to roughly 13.8% of global sales.
While much has been written of the economic advantages of Internet-enabled commerce, there is also evidence that some aspects of the internet such as maps and location-aware services may serve to reinforce economic inequality and the digital divide. Electronic commerce may be responsible for consolidation and the decline of mom-and-pop, brick and mortar businesses resulting in increases in income inequality.

Internet And Communication

Communication
Email is an important communications service available on the Internet. The concept of sending electronic text messages between parties in a way analogous to mailing letters or memos predates the creation of the Internet. Pictures, documents and other files are sent as email attachments. Emails can be cc-ed to multiple email addresses.
Internet telephony is another common communications service made possible by the creation of the Internet. VoIP stands for Voice-over-Internet Protocol, referring to the protocol that underlies all Internet communication. The idea began in the early 1990s with walkie-talkie-like voice applications for personal computers. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the voice traffic, VoIP can be free or cost much less than a traditional telephone call, especially over long distances and especially for those with always-on Internet connections such as cable or ADSL. VoIP is maturing into a competitive alternative to traditional telephone service. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple, inexpensive VoIP network adapters are available that eliminate the need for a personal computer.
Voice quality can still vary from call to call, but is often equal to and can even exceed that of traditional calls. Remaining problems for VoIP include emergency telephone number dialing and reliability. Currently, a few VoIP providers provide an emergency service, but it is not universally available. Traditional phones are line-powered and operate during a power failure; VoIP does not do so without a backup power source for the phone equipment and the Internet access devices. VoIP has also become increasingly popular for gaming applications, as a form of communication between players. Popular VoIP clients for gaming include Ventrilo and Teamspeak. Wii, PlayStation 3, and Xbox 360 also offer VoIP chat features.

Data transfer in internet

Data transfer
File sharing is an example of transferring large amounts of data across the Internet. A computer file can be emailed to customers, colleagues and friends as an attachment. It can be uploaded to a website or FTP server for easy download by others. It can be put into a "shared location" or onto a file server for instant use by colleagues. The load of bulk downloads to many users can be eased by the use of "mirror" servers or peer-to-peer networks. In any of these cases, access to the file may be controlled by user authentication, the transit of the file over the Internet may be obscured by encryption, and money may change hands for access to the file. The price can be paid by the remote charging of funds from, for example, a credit card whose details are also passed – usually fully encrypted – across the Internet. The origin and authenticity of the file received may be checked by digital signatures or by MD5 or other message digests. These simple features of the Internet, over a worldwide basis, are changing the production, sale, and distribution of anything that can be reduced to a computer file for transmission. This includes all manner of print publications, software products, news, music, film, video, photography, graphics and the other arts. This in turn has caused seismic shifts in each of the existing industries that previously controlled the production and distribution of these products.
Streaming media is the real-time delivery of digital media for the immediate consumption or enjoyment by end users. Many radio and television broadcasters provide Internet feeds of their live audio and video productions. They may also allow time-shift viewing or listening such as Preview, Classic Clips and Listen Again features. These providers have been joined by a range of pure Internet "broadcasters" who never had on-air licenses. This means that an Internet-connected device, such as a computer or something more specific, can be used to access on-line media in much the same way as was previously possible only with a television or radio receiver. The range of available types of content is much wider, from specialized technical webcasts to on-demand popular multimedia services. Podcasting is a variation on this theme, where – usually audio – material is downloaded and played back on a computer or shifted to a portable media player to be listened to on the move. These techniques using simple equipment allow anybody, with little censorship or licensing control, to broadcast audio-visual material worldwide.
Digital media streaming increases the demand for network bandwidth. For example, standard image quality needs 1 Mbit/s link speed for SD 480p, HD 720p quality requires 2.5 Mbit/s, and the top-of-the-line HDX quality needs 4.5 Mbit/s for 1080p.

Webcams are a low-cost extension of this phenomenon. While some webcams can give full-frame-rate video, the picture either is usually small or updates slowly. Internet users can watch animals around an African waterhole, ships in the Panama Canal, traffic at a local roundabout or monitor their own premises, live and in real time. Video chat rooms and video conferencing are also popular with many uses being found for personal webcams, with and without two-way sound. YouTube was founded on 15 February 2005 and is now the leading website for free streaming video with a vast number of users. It uses a flash-based web player to stream and show video files. Registered users may upload an unlimited amount of video and build their own personal profile. YouTube claims that its users watch hundreds of millions, and upload hundreds of thousands of videos daily.

Internet access

Internet access
Common methods of Internet access in homes include dial-up, landline broadband (over coaxial cable, fiber optic or copper wires), Wi-Fi, satellite and 3G/4G technology cell phones. Public places to use the Internet include libraries and Internet cafes, where computers with Internet connections are available. There are also Internet access points in many public places such as airport halls and coffee shops, in some cases just for brief use while standing. Various terms are used, such as "public Internet kiosk", "public access terminal", and "Web payphone". Many hotels now also have public terminals, though these are usually fee-based. These terminals are widely accessed for various usage like ticket booking, bank deposit, online payment etc. Wi-Fi provides wireless access to computer networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wi-Fi cafes, where would-be users need to bring their own wireless-enabled devices such as a laptop or PDA. These services may be free to all, free to customers only, or fee-based. A hotspot need not be limited to a confined location. A whole campus or park, or even an entire city can be enabled.
Grassroots efforts have led to wireless community networks. Commercial Wi-Fi services covering large city areas are in place in London, Vienna, Toronto, San Francisco, Philadelphia, Chicago and Pittsburgh. The Internet can then be accessed from such places as a park bench. Apart from Wi-Fi, there have been experiments with proprietary mobile wireless networks like Ricochet, various high-speed data services over cellular phone networks, and fixed wireless services. High-end mobile phones such as smartphones in general come with Internet access through the phone network. Web browsers such as Opera are available on these advanced handsets, which can also run a wide variety of other Internet software. More mobile phones have Internet access than PCs, though this is not as widely used. An Internet access provider and protocol matrix differentiates the methods used to get online.
An Internet blackout or outage can be caused by local signaling interruptions. Disruptions of submarine communications cables may cause blackouts or slowdowns to large areas, such as in the 2008 submarine cable disruption. Less-developed countries are more vulnerable due to a small number of high-capacity links. Land cables are also vulnerable, as in 2011 when a woman digging for scrap metal severed most connectivity for the nation of Armenia. Internet blackouts affecting almost entire countries can be achieved by governments as a form of Internet censorship, as in the blockage of the Internet in Egypt, whereby approximately 93% of networks were without access in 2011 in an attempt to stop mobilization for anti-government protests.

Global Internet usage

 Global Internet usage


Overall Internet usage has seen tremendous growth. From 2000 to 2009, the number of Internet users globally rose from 394 million to 1.858 billion. By 2010, 22 percent of the world's population had access to computers with 1 billion Google searches every day, 300 million Internet users reading blogs, and 2 billion videos viewed daily on YouTube.
The prevalent language for communication on the Internet has been English. This may be a result of the origin of the Internet, as well as the language's role as a lingua franca. Early computer systems were limited to the characters in the American Standard Code for Information Interchange (ASCII), a subset of the Latin alphabet.
After English (27%), the most requested languages on the World Wide Web are Chinese (23%), Spanish (8%), Japanese (5%), Portuguese and German (4% each), Arabic, French and Russian (3% each), and Korean (2%).[52] By region, 42% of the world's Internet users are based in Asia, 24% in Europe, 14% in North America, 10% in Latin America and the Caribbean taken together, 6% in Africa, 3% in the Middle East and 1% in Australia/Oceania.
 The Internet's technologies have developed enough in recent years, especially in the use of Unicode, that good facilities are available for development and communication in the world's widely used languages. However, some glitches such as mojibake (incorrect display of some languages' characters) still remain.
In an American study in 2005, the percentage of men using the Internet was very slightly ahead of the percentage of women, although this difference reversed in those under 30. Men logged on more often, spent more time online, and were more likely to be broadband users, whereas women tended to make more use of opportunities to communicate (such as email). Men were more likely to use the Internet to pay bills, participate in auctions, and for recreation such as downloading music and videos. Men and women were equally likely to use the Internet for shopping and banking.
More recent studies indicate that in 2008, women significantly outnumbered men on most social networking sites, such as Facebook and Myspace, although the ratios varied with age.In addition, women watched more streaming content, whereas men downloaded more. In terms of blogs, men were more likely to blog in the first place; among those who blog, men were more likely to have a professional blog, whereas women were more likely to have a personal blog.

According to Euromonitor, by 2020 43.7% of the world's population will be users of the Internet. Splitting by country, in 2011 Iceland, Norway and the Netherlands had the highest internet penetration by the number of users, with more than 90% of the population with access.

Sociology of the Internet

Sociology of the Internet

The Internet has enabled entirely new forms of social interaction, activities, and organizing, thanks to its basic features such as widespread usability and access. In the first decade of the 21st century, the first generation is raised with widespread availability of Internet connectivity, bringing consequences and concerns in areas such as personal privacy and identity, and distribution of copyrighted materials. These "digital natives" face a variety of challenges that were not present for prior generations.

Social networking and entertainment
Many people use the World Wide Web to access news, weather and sports reports, to plan and book vacations and to find out more about their interests. People use chat, messaging and email to make and stay in touch with friends worldwide, sometimes in the same way as some previously had pen pals. The Internet has seen a growing number of Web desktops, where users can access their files and settings via the Internet.

Social networking websites such as Facebook, Twitter, and MySpace have created new ways to socialize and interact. Users of these sites are able to add a wide variety of information to pages, to pursue common interests, and to connect with others. It is also possible to find existing acquaintances, to allow communication among existing groups of people. Sites like LinkedIn foster commercial and business connections. YouTube and Flickr specialize in users' videos and photographs.

The Internet has been a major outlet for leisure activity since its inception, with entertaining social experiments such as MUDs and MOOs being conducted on university servers, and humor-related Usenet groups receiving much traffic. Today, many Internet forums have sections devoted to games and funny videos; short cartoons in the form of Flash movies are also popular. Over 6 million people use blogs or message boards as a means of communication and for the sharing of ideas. The internet pornography and online gambling industries have taken advantage of the World Wide Web, and often provide a significant source of advertising revenue for other websites. Although many governments have attempted to restrict both industries' use of the Internet, in general this has failed to stop their widespread popularity.

Another area of leisure activity on the Internet is multiplayer gaming.This form of recreation creates communities, where people of all ages and origins enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters, from role-playing video games to online gambling. While online gaming has been around since the 1970s, modern modes of online gaming began with subscription services such as GameSpy and MPlayer. Non-subscribers were limited to certain types of game play or certain games. Many people use the Internet to access and download music, movies and other works for their enjoyment and relaxation. Free and fee-based services exist for all of these activities, using centralized servers and distributed peer-to-peer technologies. Some of these sources exercise more care with respect to the original artists' copyrights than others.

Internet usage has been correlated to users' loneliness.Lonely people tend to use the Internet as an outlet for their feelings and to share their stories with others, such as in the "I am lonely will anyone speak to me" thread.

Cybersectarianism is a new organizational form which involves: "highly dispersed small groups of practitioners that may remain largely anonymous within the larger social context and operate in relative secrecy, while still linked remotely to a larger network of believers who share a set of practices and texts, and often a common devotion to a particular leader. Overseas supporters provide funding and support; domestic practitioners distribute tracts, participate in acts of resistance, and share information on the internal situation with outsiders. Collectively, members and practitioners of such sects construct viable virtual communities of faith, exchanging personal testimonies and engaging in collective study via email, on-line chat rooms and web-based message boards."

Cyberslacking can become a drain on corporate resources; the average UK employee spent 57 minutes a day surfing the Web while at work, according to a 2003 study by Peninsula Business Services. Internet addiction disorder is excessive computer use that interferes with daily life. Psychologist Nicolas Carr believe that Internet use has other effects on individuals, for instance improving skills of scan-reading and interfering with the deep thinking that leads to true creativity.

Services of World Wide Web in internet

Many people use the terms Internet and World Wide Web, or just the Web, interchangeably, but the two terms are not synonymous. The World Wide Web is a global set of documents, images and other resources, logically interrelated by hyperlinks and referenced with Uniform Resource Identifiers (URIs). URIs symbolically identify services, servers, and other databases, and the documents and resources that they can provide. Hypertext Transfer Protocol (HTTP) is the main access protocol of the World Wide Web, but it is only one of the hundreds of communication protocols used on the Internet. Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data.
World Wide Web browser software, such as Microsoft's Internet Explorer, Mozilla Firefox, Opera, Apple's Safari, and Google Chrome, lets users navigate from one web page to another via hyperlinks embedded in the documents. These documents may also contain any combination of computer data, including graphics, sounds, text, video, multimedia and interactive content that runs while the user is interacting with the page. Client-side software can include animations, games, office applications and scientific demonstrations. Through keyword-driven Internet research using search engines like Yahoo! and Google, users worldwide have easy, instant access to a vast and diverse amount of online information. Compared to printed media, books, encyclopedias and traditional libraries, the World Wide Web has enabled the decentralization of information on a large scale.
The Web has also enabled individuals and organizations to publish ideas and information to a potentially large audience online at greatly reduced expense and time delay. Publishing a web page, a blog, or building a website involves little initial cost and many cost-free services are available. Publishing and maintaining large, professional web sites with attractive, diverse and up-to-date information is still a difficult and expensive proposition, however. Many individuals and some companies and groups use web logs or blogs, which are largely used as easily updatable online diaries. Some commercial organizations encourage staff to communicate advice in their areas of specialization in the hope that visitors will be impressed by the expert knowledge and free information, and be attracted to the corporation as a result. One example of this practice is Microsoft, whose product developers publish their personal blogs in order to pique the public's interest in their work. Collections of personal web pages published by large service providers remain popular, and have become increasingly sophisticated. Whereas operations such as Angelfire and GeoCities have existed since the early days of the Web, newer offerings from, for example, Facebook and Twitter currently have large followings. These operations often brand themselves as social network services rather than simply as web page hosts.
Advertising on popular web pages can be lucrative, and e-commerce or the sale of products and services directly via the Web continues to grow.
When the Web began in the 1990s, a typical web page was stored in completed form on a web server, formatted in HTML, ready to be sent to a user's browser in response to a request. Over time, the process of creating and serving web pages has become more automated and more dynamic. Websites are often created using content management or wiki software with, initially, very little content. Contributors to these systems, who may be paid staff, members of a club or other organization or members of the public, fill underlying databases with content using editing pages designed for that purpose, while casual visitors view and read this content in its final HTML form. There may or may not be editorial, approval and security systems built into the process of taking newly entered content and making it available to the target visitors.