Tim Berners-Lee

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Posted by kaori 04/23/2009 @ 22:15

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News headlines
Tim Berners-Lee gives first insight into government data plan - Computing
In a paper entitled Putting government data online, Berners-Lee says he favours the use of Linked Data as a means of publishing information. Linked Data is part of the Semantic Web – another Berners-Lee initiative to make information on the internet...
Happy Birthday Sir Tim Berners-Lee, Inventor of the World Wide Web - findingDulcinea
by Haley A. Lovett Known as the inventor of the World Wide Web, Sir Tim Berners-Lee's work to develop html, http, and the url system changed the way the world used computers. Today Berners-Lee continues his work with the Internet, now focused on...
Berners-Lee: Web could cure cancer and halt climate change - The Tech Herald
The Web still has great things to give, according to Sir Tim Berners-Lee. Image: Silvio Tanaka/Flickr. Specifically, Sir Tim Berners-Lee, the man credited with creating the Web as we know it, has said he sees the Internet contributing heavily towards...
Journalism's future and 5 minutes with Sir Tim - The Zonie Report
Thankfully, Sir Tim Berners-Lee – the guy who conceptualized the World Wide Web – was in attendance. So I went straight to him – as did everyone else – for an answer. A short introduction. And then, “So Tim – what is your take on the idea that context...
Government outlines Berners-Lee's role - ZDNet UK
Over the next six months, Sir Tim Berners-Lee will oversee the implementation of key recommendations from the government's Power of Information report. These include: creating the beta site for a single online point of access for all public sector...
Rice scientist wins highest IEEE honor - Bizjournals.com
Past winners of the award include: Intel Corp. co-founder Gordon Moore (1978); microprocessor inventor Federico Faggin (1994); World Wide Web inventor Tim Berners-Lee (1996); Lotus Notes creator and Microsoft chief software architect Ray Ozzie (2000);...
Things that tweet - BBC News
Sir Tim Berners-Lee has spent many years talking about a machine-readable web, and it looks as though the machines - that is, computers - may well end up "reading" about the activities of other machines. I sat musing on this at my kitchen table,...
Friday Poll: And for Twitter's next trick... - CNET News
(HTML was a no brainer if you were Tim Berners Lee, eg) by Seaspray0 June 19, 2009 1:04 PM PDT I didn't bash it. I just said that I don't have any interest in social networks. by sanenazok June 19, 2009 6:55 PM PDT @cosuna: It's fine for Twitter to be...
Let Sir Tim lead the fight for free data - guardian.co.uk
Mandelson's Department for Business and Nearly Everything Else, it's just as well that Sir Tim Berners-Lee – at the time of writing, not ennobled – doesn't have a TV show. Not even one teaching us to do semantic web analysis....
Firing up the next generation of international tech businesses - UK Trade & Investment
Just look at how integral the World Wide Web, developed by British inventor Tim Berners Lee, is to business. With more spin-out companies emerging from UK universities than their US counterparts we must equip the uk's next generation of technology...

Tim Berners-Lee

Tim Berners-Lee CP.jpg

Sir Timothy John Berners-Lee, OM, KBE, FRS, FREng, FRSA (London, 8 June 1955) is an English computer scientist and MIT professor credited with inventing the World Wide Web. On 25 December 1990 he implemented the first successful communication between an HTTP client and server via the Internet with the help of Robert Cailliau and a young student staff at CERN. In 2007, he was ranked Joint First alongside Albert Hofmann in The Telegraph's list of 100 greatest living geniuses. Berners-Lee is the director of the World Wide Web Consortium (W3C), which oversees the Web's continued development, the founder of the World Wide Web Foundation and he is a senior researcher and holder of the 3Com Founders Chair at the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL).

Tim Berners-Lee was born in London, England on 8 June 1955. He attended Emanuel School in London from 1969 to 1973, and studied at The Queen's College, Oxford University, from 1973 to 1976, where he received his BA Hons (I) in Physics.

While an independent contractor at CERN from June to December 1980, Berners-Lee proposed a project based on the concept of hypertext, to facilitate sharing and updating information among researchers. While there, he built a prototype system named ENQUIRE. After leaving CERN in 1980 he went to work at John Poole's Image Computer Systems Ltd in Bournemouth but returned to CERN in 1984 as a fellow. In 1989, CERN was the largest Internet node in Europe, and Berners-Lee saw an opportunity to join hypertext with the Internet: "I just had to take the hypertext idea and connect it to the Transmission Control Protocol and domain name system ideas and — ta-da! — the World Wide Web." He wrote his initial proposal in March 1989, and in 1990, with the help of Robert Cailliau, produced a revision which was accepted by his manager, Mike Sendall. He used similar ideas to those underlying the Enquire system to create the World Wide Web, for which he designed and built the first web browser and editor (WorldWideWeb, running on the NeXTSTEP operating system) and the first Web server, CERN HTTPd (short for HyperText Transfer Protocol daemon).

The first Web site built was at CERN and was first put online on 6 August 1991. It provided an explanation about what the World Wide Web was, how one could own a browser and how to set up a Web server. It was also the world's first Web directory, since Berners-Lee maintained a list of other Web sites apart from his own.

In 1994, Berners-Lee founded the World Wide Web Consortium (W3C) at the Massachusetts Institute of Technology. It comprised various companies that were willing to create standards and recommendations to improve the quality of the Web. Berners-Lee made his idea available freely, with no patent and no royalties due. The World Wide Web Consortium decided that their standards must be based on royalty-free technology, so they can be easily adopted by anyone.

In 2001, Berners-Lee became a patron of the East Dorset Heritage Trust having previously lived in Colehill in Wimborne, East Dorset, England.

In December 2004 he accepted a chair in Computer Science at the School of Electronics and Computer Science, University of Southampton, England, to work on his new project—the Semantic Web.

He was also one of the pioneer voices in favor of Net Neutrality.

He feels that ISPs should not intercept customers' browsing activities, and has such strong views about this that he would change ISPs to get away from such activities.

Berners-Lee is currently the Director of the W3C and also at the Massachusetts Institute of Technology the 3Com Founders Professor in the School of Engineering and at the Computer Science and Artificial Intelligence Laboratory (MIT CSAIL). He is also a director of The Web Science Research Initiative (WSRI), and a member of the advisory board of the MIT Center for Collective Intelligence.

Berners-Lee left the Church of England, a religion in which he had been brought up, as a teenager just after being confirmed because he could not "believe in all kinds of unbelievable things." He and his family eventually found a Unitarian Universalist church while they were living in Boston.

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Hypertext is text, displayed on a computer, with references (hyperlinks) to other text that the reader can immediately follow, usually by a mouse click or keypress sequence. Apart from running text, hypertext may contain tables, images and other presentational devices. Any of these can be hyperlinks; other means of interaction may also be present, e.g. a bubble with text may appear when the mouse hovers somewhere, a video clip may be started and stopped, or a form may be filled out and submitted.

The most extensive example of hypertext today is the World Wide Web.

Hypertext documents can either be static (prepared and stored in advance) or dynamic (continually changing in response to user input). Static hypertext can be used to cross-reference collections of data in documents, software applications, or books on CDs. A well-constructed system can also incorporate other user-interface conventions, such as menus and command lines. Hypertext can develop very complex and dynamic systems of linking and cross-referencing. The most famous implementation of hypertext is the World Wide Web (first deployed in 1992) and later added to the Internet (developed/tested c.1977).

Recorders of information have long looked for ways to categorize and compile it. Early on, experiments existed with various methods for arranging layers of annotations around a document. The most famous example of this is the Talmud. Other reference works (for example dictionaries, encyclopedias, etc.) also developed a precursor to hypertext, consisting of setting certain words in small capital letters, indicating that an entry existed for that term within the same reference work. Sometimes the term would be preceded by an index, ☞like this, or an arrow, ➧like this.

Later, several scholars entered the scene who believed that humanity was drowning in information, causing foolish decisions and duplicating efforts among scientists. These scholars proposed or developed proto-hypertext systems predating electronic computer technology. For example, in the early 20th century, two visionaries attacked the cross-referencing problem through proposals based on labor-intensive, brute force methods. Paul Otlet proposed a proto-hypertext concept based on his monographic principle, in which all documents would be decomposed down to unique phrases stored on index cards. In the 1930s, H.G. Wells proposed the creation of a World Brain.

Michael Buckland summarized the very advanced pre-World War II development of microfilm based on rapid retrieval devices, specifically the microfilm based workstation proposed by Leonard Townsend in 1938 and the microfilm and photoelectronic based selector, patented by Emanuel Goldberg in 1931. Buckland concluded: "The pre-war information retrieval specialists of continental Europe, the 'documentalists,' largely disregarded by post-war information retrieval specialists, had ideas that were considerably more advanced than is now generally realized." But, like the manual index card model, these microfilm devices provided rapid retrieval based on pre-coded indices and classification schemes published as part of the microfilm record without including the link model which distinguishes the modern concept of hypertext from content or category based information retrieval.

All major histories of what we now call hypertext start in 1945, when Vannevar Bush wrote an article in The Atlantic Monthly called "As We May Think", about a futuristic device he called a Memex. He described the device as an electromechanical desk linked to an extensive archive of microfilms, able to display books, writings, or any document from a library. The Memex would also be able to create 'trails' of linked and branching sets of pages, combining pages from the published microfilm library with personal annotations or additions captured on a microfilm recorder. Bush's vision was based on extensions of 1945 technology - microfilm recording and retrieval in this case. However, the modern story of hypertext starts with the Memex because "As We May Think" directly influenced and inspired the two American men generally credited with the invention of hypertext, Ted Nelson and Douglas Engelbart.

Ted Nelson coined the words "hypertext" and "hypermedia" in 1965 and worked with Andries van Dam to develop the Hypertext Editing System in 1968 at Brown University. Engelbart had begun working on his NLS system in 1962 at Stanford Research Institute, although delays in obtaining funding, personnel, and equipment meant that its key features were not completed until 1968. In December of that year, Engelbart demonstrated a hypertext interface to the public for the first time, in what has come to be known as "The Mother of All Demos".

Funding for NLS slowed after 1974. Influential work in the following decade included NoteCards at Xerox PARC and ZOG at Carnegie Mellon. ZOG started in 1972 as an artificial intelligence research project under the supervision of Allen Newell, and pioneered the "frame" or "card" model of hypertext. ZOG was deployed in 1982 on the U.S.S. Carl Vinson and later commercialized as Knowledge Management System. Two other influential hypertext projects from the early 1980s were Ben Shneiderman's The Interactive Encyclopedia System (TIES) at the University of Maryland (1983) and Intermedia at Brown University (1984).

The first hypermedia application was the Aspen Movie Map in 1977. In 1980, Tim Berners-Lee created ENQUIRE, an early hypertext database system somewhat like a wiki. The early 1980s also saw a number of experimental hypertext and hypermedia programs, many of whose features and terminology were later integrated into the Web. Guide was the first hypertext system for personal computers.

In August 1987, Apple Computer released HyperCard for the Macintosh line at the MacWorld convention. Its impact, combined with interest in Peter J. Brown's GUIDE (marketed by OWL and released earlier that year) and Brown University's Intermedia, led to broad interest in and enthusiasm for hypertext and new media. The first ACM Hypertext academic conference took place in November 1987, in Chapel Hill NC.

Meanwhile Nelson, who had been working on and advocating his Xanadu system for over two decades, along with the commercial success of HyperCard, stirred Autodesk to invest in his revolutionary ideas. The project continued at Autodesk for four years, but no product was released.

In the late 1980s, Berners-Lee, then a scientist at CERN, invented the World Wide Web to meet the demand for automatic information-sharing among scientists working in different universities and institutes all over the world. In 1992, Lynx was born as an early Internet web browser. Its ability to provide hypertext links within documents that could reach into documents anywhere on the Internet began the creation of the web on the Internet.

Early in 1993, the National Center for Supercomputing Applications (NCSA) at the University of Illinois released the first version of their Mosaic web browser to supplement the two existing web browsers: one that ran only on NeXTSTEP and one that was only minimally user-friendly. Because it could display and link graphics as well as text, Mosaic quickly became the replacement for Lynx. Mosaic ran in the X Window System environment, which was then popular in the research community, and offered usable window-based interactions. It allowed images as well as text to anchor hypertext links. It also incorporated other protocols intended to coordinate information across the Internet, such as Gopher.

After the release of web browsers for both the PC and Macintosh environments, traffic on the World Wide Web quickly exploded from only 500 known web servers in 1993 to over 10,000 in 1994. Thus, all earlier hypertext systems were overshadowed by the success of the web, even though it originally lacked many features of those earlier systems, such as an easy way to edit what you were reading, typed links, backlinks, transclusion, and source tracking.

In 1995, Ward Cunningham made the first wiki available, making the web more hypertextual by adding easy editing, and (within a single wiki) backlinks and limited source tracking. It also added the innovation of making it possible to link to pages that did not yet exist. Wiki developers continue to implement novel features as well as those developed or imagined in the early explorations of hypertext but not included in the original web.

The Firefox Add-On Hyperwords which has been developed in cooperation with Doug Engelbart and Ted Nelson gives Web surfers the ability to issue many commands on any text on the web, not only pre-written links - a return to what users could do 40 years earlier with Doug Engelbart's NLS.

Among the top academic conferences for new research in hypertext is the annual ACM Conference on Hypertext and Hypermedia ( ACM SIGWEB Hypertext Conference page). Although not exclusively about hypertext, the World Wide Web series of conferences, organized by IW3C2, include many papers of interest. There is a list on the web with links to all conferences in the series.

Hypertext writing has developed its own style of fiction, coinciding with the growth and proliferation of hypertext development software and the emergence of electronic networks. Two software programs specifically designed for literary hypertext, Storyspace and Intermedia became available in the 1990s.

Storyspace 2.0, a professional level hypertext development tool, is available from Eastgate Systems, which has also published many notable works of electronic literature, including Michael Joyce's afternoon, a story, Shelley Jackson's Patchwork Girl, Stuart Moulthrop's Victory Garden, and Judy Malloy's its name was Penelope. Other works include Julio Cortázar's Rayuela and Milorad Pavić's Dictionary of the Khazars.

An advantage of writing a narrative using hypertext technology is that the meaning of the story can be conveyed through a sense of spatiality and perspective that is arguably unique to digitally-networked environments. An author's creative use of nodes, the self-contained units of meaning in a hypertextual narrative, can play with the reader's orientation and add meaning to the text.

Critics of hypertext claim that it inhibits the old, linear, reader experience by creating several different tracks to read on, and that this in turn contributes to a postmodernist fragmentation of worlds. In some cases, hypertext can be more a problem to get appealing stories than a tool to develop creativity. However, they do see value in its ability to present several different views on the same subject in a simple way.. This echoes the arguments of 'medium theorists' like Marshall McLuhan who look at the social and psychological impacts of the media. New media can become so dominant in public culture that they effectively create a "paradigm shift" (Lelia Green, 2001:15) as people have shifted their perceptions, understanding of the world and ways of interacting with the world and each other in relation to new technologies and medias. So hypertext signifies a change from linear, structured and hierarchical forms of representing and understanding the world into fractured, decentralized and changeable medias based on the technological concept of hypertext links.

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World Wide Web

This NeXT Computer used by Sir Tim Berners-Lee at CERN became the first Web server.

The World Wide Web (commonly abbreviated as "the Web") is an elaborate set 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 using hyperlinks. Using concepts from earlier hypertext systems, the World Wide Web was started in 1989 by the English physicist Sir Tim Berners-Lee, now the Director of the World Wide Web Consortium, and later by Robert Cailliau, a Belgian computer scientist, while both were working at CERN in Geneva, Switzerland. In 1990, they proposed building a "web of nodes" storing "hypertext pages" viewed by "browsers" on a network, and released that web in December. Connected by the existing Internet, other websites were created, around the world, adding international standards for domain names & the HTML language. 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 an application built on top of the Internet.

The underlying ideas of the Web can be traced as far back as 1980, when, at CERN in Switzerland, Sir Tim Berners-Lee built ENQUIRE (a reference to Enquire Within Upon Everything, a book he recalled from his youth). While it was rather different from the system in use today, it contained many of the same core ideas (and even some of the ideas of Berners-Lee's next project after the World Wide Web, the Semantic Web).

In March 1989, Berners-Lee wrote a proposal which referenced ENQUIRE and described a more elaborate information management system. With help from Robert Cailliau, he published a more formal proposal (on November 12, 1990) to build a "Hypertext project" called "WorldWideWeb" (one word, also "W3") as a "web of nodes" with "hypertext documents" to store data. That data would be viewed in "hypertext pages" (webpages) by various "browsers" (line-mode or full-screen) on the computer network, using an "access protocol" connecting the "Internet and DECnet protocol worlds".

The proposal had been modeled after EBT's (Electronic Book Technology, a spin-off from the Institute for Research in Information and Scholarship at Brown University) Dynatext SGML reader that CERN had licensed. The Dynatext system, although technically advanced (a key player in the extension of SGML ISO 8879:1986 to Hypermedia within HyTime), was considered too expensive and with an inappropriate licensing policy for general HEP (High Energy Physics) community use: a fee for each document and each time a document was changed.

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 August 6, 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.

The first server outside Europe was set up at SLAC in December 1991.

The crucial underlying concept of hypertext originated with older projects from the 1960s, such as the Hypertext Editing System (HES) at Brown University--- among others Ted Nelson and Andries van Dam--- 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 a system of globally unique identifiers for resources on the Web and elsewhere: the Uniform Resource Identifier.

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 April 30, 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 Gopher (protocol) 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, which was based upon HyperCard.

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, a funding program initiated by 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 its 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—and the European Commission.

The terms Internet and World Wide Web are often used in every-day speech without much distinction. However, the Internet and the World Wide Web are not one and the same. The Internet is a global data communications system. It is a hardware and software infrastructure that provides connectivity between computers. In contrast, the Web is one of the services communicated via the Internet. It is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. In short, the Web is 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.

Traditionally, each chunk of information sent by a web server to a browser must be explicitly requested. Each time the user opens a new web page, the browser initiates an HTTP connection to the web server. The browser requests a page for which the server returns the HTML code and waits for more requests on the same connection. The browser typically makes multiple HTTP requests, for each resource used by the page the server responds with data, e.g. images and stylesheets. For example Wikipedia is a web application built using this page-by-page web model.

First, the server-name portion of the URL is resolved into an IP address using the global, distributed Internet database known as the domain name system, or DNS. This IP address is necessary to contact and send data packets to the Web server. The browser then requests the resource by sending an HTTP request to the Web server at that particular address. In the case of a typical Web page, the HTML text of the page is requested first and parsed immediately by the Web browser, which will then make additional requests for images and any other files that form a part of the page. Statistics measuring a website's popularity are usually based on the number of 'page views' or associated server 'hits', or file requests, which take place.

Having received the required files from the Web server, the browser then renders the page onto the screen as specified by its HTML, CSS, and other Web languages. Any images and other resources are incorporated to produce the on-screen Web page that the user sees.

Most Web pages will themselves contain hyperlinks to other related pages and perhaps to downloads, source documents, definitions and other Web resources. Such a collection of useful, related resources, interconnected via hypertext links, is what was dubbed a "web" of information. Making it available on the Internet created what Tim Berners-Lee first called the WorldWideWeb (in its original CamelCase, which was subsequently discarded) in November 1990.

To overcome some of the limitations of the page-by-page model, some web applications use Ajax (asynchronous JavaScript and XML). JavaScript delivered with the page makes additional HTTP requests to the server, either in response to user actions such as mouse-clicks, or based on timers. The server's responses are used to modify the current page rather than creating a new page for each request. Thus the server only needs to provide limited, incremental information. Since multiple Ajax requests can be handled at the same time, users can interact with a page even while data is being retrieved. Some web applications regularly poll the server to ask if new information is available. High polling rates can waste server resources and bandwidth but web applications with relatively few users can use polling without significant overhead.

Netscape introduced “server push” technology, where the server would constantly send new data to the client through the initial connection, that remains open. This was made possible by the use of server side programming and by the multipart feature of the MIME standard.

The letters "www" are commonly found at the beginning of Web addresses because of the long-standing practice of naming Internet hosts (servers) according to the services they provide. So for example, the host name for a Web server is often "www"; for an FTP server, "ftp"; and for a USENET news server, "news" or "nntp" (after the news protocol NNTP). These host names appear as DNS subdomain names, as in "www.example.com".

This use of such prefixes is not required by any technical standard; indeed, the first Web server was at "nxoc01.cern.ch", and even today many Web sites exist without a "www" prefix. The "www" prefix has no meaning in the way the main Web site is shown. The "www" prefix is simply one choice for a Web site's host name.

However, some website addresses require the www. prefix, and if typed without one, won't work; there are also some which must be typed without the prefix. Sites that do not have Host Headers properly setup are the cause of this. Some hosting companies do not set up a www or @ A record in the web server configuration and/or at the DNS server level.

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.

It is also interesting that 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 capitalized, with no intervening hyphens. Additionally, 'Web' (with a capital 'W') is used to indicate its status as an abbreviation.

Many formal standards and other technical specifications 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.

Computer users, who save time and money, and who gain conveniences and entertainment, may or may not have surrendered the right to privacy in exchange for using a number of technologies including the Web. Worldwide, more than a half billion people have used a social network service, and of Americans who grew up with the Web, half created an online profile and are part of a generational shift that could be changing norms. Facebook progressed from U.S. college students to a 70% non-U.S. audience and estimates that only 20% of its members use privacy settings.

Privacy representatives from 60 countries have resolved to ask for laws to complement industry self-regulation, for education for children and other minors who use the Web, and for default protections for users of social networks. They also believe data protection for personally identifiable information benefits business more than the sale of that information. Users can opt-in to features in browsers to clear their personal histories locally and block some cookies and advertising networks but they are still tracked in websites' server logs, and particularly Web beacons. Berners-Lee and colleagues see hope in accountability and appropriate use achieved by extending the Web's architecture to policy awareness, perhaps with audit logging, reasoners and appliances.

Among services paid for by advertising, Yahoo! could collect the most data about users of commercial websites, about 2,500 bits of information per month about each typical user of its site and its affiliated advertising network sites. Yahoo! was followed by MySpace with about half that potential and then by AOL-TimeWarner, Google, Facebook, Microsoft, and eBay.

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.

In terms of security as it relates to the 'physical' portion of the World Wide Web/Internet, the 'distributed' nature of the Internet provides security against attack -- as there is no one single 'focus point' through which all Internet traffic is directed, any attempt to 'cripple' the Internet would only disable a small portion of the whole, and the connecting computers would simply direct the affected traffic through other, unaffected networks and computers.

Access to the Web is for everyone regardless of disability including visual, auditory, physical, speech, cognitive, and neurological. Accessibility features also help others with temporary disabilities like a broken arm and an aging population as their abilities change. The Web is used for receiving information as well as providing information and interacting with society, making it essential that the Web be accessible in order to provide equal access and equal opportunity to people with disabilities.

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.

The W3C Internationalization Activity assures that Web technology will work in all languages, scripts, and cultures. Beginning in 2004 or 2005, Unicode gained ground and eventually in December 2007 surpassed both ASCII and Western European as the Web's most frequently used character encoding. Originally RFC 3986 allowed resources to be identified by URI in a subset of US-ASCII. RFC 3987 allows more characters—any character in the Universal Character Set (Unicode/ISO 10646)—and now a resource can be idenfified by IRI in any language.

According to a 2001 study, there were massively more than 550 billion 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 English: 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 July 25, 2008, Google software engineers Jesse Alpert and Nissan Hajaj announced that Google Search had discovered one trillion unique URLs.

Over 100.1 million websites operated as of March 2008. Of these 74% were commercial or other sites operating in the .com generic top-level domain.

Frustration over congestion issues in the Internet infrastructure and the high latency that results in slow browsing has led to an alternative, pejorative name for the World Wide Web: the World Wide Wait. Speeding up the Internet is an ongoing discussion over the use of peering and QoS technologies. Other solutions to reduce the World Wide Wait can be found at W3C.

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 only ask for data that has changed since the last download. If the locally-cached data are still current, it 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 whatever other content the site may provide. Thus even on sites with highly dynamic content, many of the basic resources only need to be refreshed 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, such as Google or Yahoo!, 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.

Over time, many Web resources pointed to by hyperlinks disappear, relocate, or are replaced with different content. This phenomenon is 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 is one of the most well-known efforts; it has been active since 1996.

Web pages are composed of HTML and may include text, multimedia, hyperlinks, and other multimedia.

Java (software platform) enables Web pages to embed small programs (called applets) directly into the view. These applets run on the end-user's computer, providing a richer user interface than simple Web pages. Java client-side applets never gained the popularity that Sun had hoped for a variety of reasons, including lack of integration with other content (applets were confined to small boxes within the rendered page) and the fact that many computers at the time were supplied to end users without a suitably installed Java Virtual Machine, and so required a download by the user before applets would appear. Adobe Flash now performs many of the functions that were originally envisioned for Java applets, including the playing of video content, animation, and some rich GUI features. Java itself has become more widely used as a platform and language for server-side and other programming.

JavaScript, on the other hand, is a scripting language that was initially developed for use within Web pages. The standardized version is ECMAScript. While its name is similar to Java, JavaScript was developed by Netscape and has very little to do with Java, although the syntax of both languages is derived from the C programming language. In conjunction with a Web page's Document Object Model (DOM), JavaScript has become a much more powerful technology than its creators originally envisioned. The manipulation of a page's DOM after the page is delivered to the client has been called Dynamic HTML (DHTML), to emphasize a shift away from static HTML displays.

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Web-based Distributed Authoring and Versioning, or WebDAV, is a set of extensions to the Hypertext Transfer Protocol (HTTP) that allows users to edit and manage files collaboratively on remote World Wide Web servers. The group of developers responsible for these extensions was also known by the same name and was a working group of the Internet Engineering Task Force (IETF).

The WebDAV protocol allows "Intercreativity," making the Web a readable and writable medium, in line with Tim Berners-Lee's original vision. It allows users to create, change and move documents on a remote server (typically a web server or "web share"). This is useful for authoring the documents that a web server serves, but it can also be used for storing files on the web, so that the files can be accessed from anywhere. The most important features of the WebDAV protocol are: locking ("overwrite prevention"); properties (creation, removal, and querying of information about author, modified date, etc.); name space management (ability to copy and move Web pages within a server's namespace); and collections (creation, removal, and listing of resources). Most modern operating systems provide built-in support for WebDAV. With a fast network and the right client, it is almost as easy to use files on a WebDAV server as those stored in local directories.

The WebDAV working group concluded its work in March 2007, after an incremental update to RFC 2518 was accepted by the Internet Engineering Steering Group (IESG). Other extensions that were unfinished at that time, such as the BIND method, will be finished by their individual authors, independent of the formal working group.

WebDAV began in 1996 when Jim Whitehead worked with the World Wide Web Consortium (W3C) to host two meetings to discuss the problem of distributed authoring on the World Wide Web with interested people. The original vision of the Web as expounded by Tim Berners-Lee was a both readable and writable medium. In fact Berners-Lee's first web browser, called WorldWideWeb, was able to both view and edit web pages; but, as the Web grew, it became, for most users, a read-only medium. Whitehead and other like-minded people wanted to fix that limitation.

At the W3C meeting, it was decided that the best way to proceed was to form an IETF working group, because the new effort would lead to extensions to HTTP, which was being standardized at the IETF.

As work began on the protocol, it became clear that handling both distributed authoring and versioning was too much work and that the tasks would have to be separated. The WebDAV group focused on distributed authoring, and left versioning for the future. Versioning was added later by the Delta-V extension — see the Extensions section below.

In addition, WebDAV over HTTPS works only if KB892211-version files or newer are installed on the computer. Otherwise Windows displays "The folder you entered does not appear to be valid. Please choose another" when adding a network resource.

In Windows Vista, only the WebDAV redirector is present; the original "Web folders" client has been removed. The "Web folders" client is only present if the Microsoft Update for Web Folders is installed. This will only work on the 32bit version of Vista.

WebDAV shares have been supported natively as a type of filesystem since Mac OS X version 10.0. The system can mount WebDAV-enabled server directories to the filesystem using the traditional BSD mounting mechanism. Mac OS X version 10.1.1 introduced support for HTTP Digest Access authentication. Mac OS X 10.4 (Tiger) extended WebDAV interoperability to include support for the https scheme, proxies, and additional methods of authentication.

The Finder presents a WebDAV share as an external disk, allowing users to interact with WebDAV just like they would any other filesystem. Apple's iDisk uses WebDAV for file access.

WebDAV shares can be mounted in Linux using davfs2 or fusedav which mount them as coda or FUSE filesystems. Konqueror and Nautilus have WebDAV support built in. A WebDAV command line client for Unix with an FTP-like command set called Cadaver is included in many Linux distributions.

Most of the work was put into developing the WebDAV specifications and recommendations in the late 1990s and since that time many other approaches to solving the same and similar problems have developed. WebDAV is an approach to what would now be called 'content management'.

Many content management systems now exist (CMS), with either proprietary or open on-line APIs that provide similar functionality to WebDAV.

Remote content can still be managed by the traditional methods based on FTP and its derivatives. Versioning and file-locking is also available as part of most revision control systems such as CVS and Subversion (SVN) (which happens to use WebDAV as one of its transports).

The SMB protocol allows Microsoft Windows and open-source Samba clients to access and manage files and folders remotely on a suitable file server. More recently, Microsoft introduced and developed a range of SharePoint server products that also allow remote authors to manage lists and folders of remote, shared files.

The HTTP, web service APIs of CMS, Wiki, blog, revision control and other modern, remote, collaborative authoring and versioning systems may be based on XML SOAP, which uses the HTTP 'POST' and 'GET' verbs almost exclusively. Alternatively, they may use RESTful techniques, so that in addition to 'GET' and 'POST', other HTTP verbs such as 'PUT' and 'DELETE' also get used meaningfully, in ways that are comparable to WebDAV. Note that WebDAV also specifies more specialised verbs such as 'COPY', 'MOVE', 'LOCK' etc., as described above.

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Source : Wikipedia