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World Wide Web (WWW), system of resources that enable computer users to view and interact with a variety of information, including magazine archives, public- and university-library resources, current world and business news, and software programs. The WWW can be accessed by a computer connected to an internet, an interconnection of computer networks or through the public Internet, the global consortium of interconnected computer networks. WWW resources are organized to allow users to move easily from one resource to another. Users generally navigate through the WWW using an application known as a WWW browser client. The browser presents formatted text, images, sound, or other objects, such as hyperlinks, in the form of a WWW page on a computer screen. The user can click on a hyperlink with the cursor to navigate to other WWW pages on the same source computer, or server, or on any other WWW server on the network. The WWW links exist across the global Internet to form a large-scale, distributed, multimedia knowledge base that relates words, phrases, images, or other information. Smaller-scale implementations may occur on enterprise internets. WWW pages are formatted using Hypertext Markup Language (HTML), and information is transferred among computers on the WWW using a set of rules known as Hypertext Transfer Protocol (HTTP). Other features may be added to web pages with special programs, such as Java, a programming language that is independent of a computer's operating system, developed by Sun Microsystems. Java-enabled web browsers use applets that run within the context of HTML-formatted documents. With applets it is possible to add animation and greater interactively to web pages. The World Wide Web was developed in 1989 by English computer scientist Timothy Berners-Lee to enable information to be shared among internationally dispersed teams of researchers at the European Laboratory for Particle Physics (formerly known by the acronym CERN) near Geneva, Switzerland. It subsequently became a platform for related software development, and the numbers of linked computers and users grew rapidly to support a variety of endeavors, including a large business marketplace. Its further development is guided by the WWW Consortium based at the Massachusetts Institute of Technology in Cambridge, Massachusetts.
Web Site, in computer science, file of information located on a server connected to the World Wide Web (WWW). The WWW is a set of protocols and software that allows the global computer network called the Internet to display multimedia documents. Web sites may include text, photographs, illustrations, video, music, or computer programs. They also often include links to other sites in the form of hypertext, highlighted or colored text that the user can click on with their mouse, instructing their computer to jump to the new site. Every web site has a specific address on the WWW, called a Uniform Resource Locator (URL). These addresses end in extensions that indicate the type of organization sponsoring the web site, for example, .gov for government agencies, .edu for academic institutions, and .com for commercial enterprises. The user’s computer must be connected to the Internet and have a special software program called a browser to retrieve and read information from a web site. Examples of browsers include Navigator from the Netscape Communications Corporation and Explorer from the Microsoft Corporation. The content presented on a web site usually contains hypertext and icons, pictures that also serve as links to other sites. By clicking on the hypertext or icons with their mouse, users instruct their browser program to connect to the web site specified by the URL contained in the hypertext link. These links are embedded in the web site through the use of Hypertext Markup Language (HTML), a special language that encodes the links with the correct URL. Web sites generally offer an appearance that resembles the graphical user interfaces (GUI) of Microsoft’s Windows operating system, Apple’s Macintosh operating system, and other graphics based operating systems. They may include scroll bars, menus, buttons, icons, and toolbars, all of which can be activated by a mouse or other input device. To find a web site, a user can consult an Internet reference guide or directory, or use one of the many freely available search engines, such as WebCrawler from America Online Incorporated. These engines are search and retrieval programs, of varying sophistication, that ask the user to fill out a form before executing a search of the WWW for the requested information. The user can also create a list of the URLs of frequently visited web sites. Such a list helps a user recall a URL and easily access the desired web site. Web sites are easily modified and updated, so the content of many sites changes frequently.
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