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The Internet was not discussed by the popular press much before 1990. However, the Internet origins date back to 1970 when four computers --- one each at the Stanford Research Institute, the University of California at Los Angeles, The University of California at Santa Barbara, and the University of Utah at Salt Lake city – were first hooked up to each other over telephone lines. From this very small network, we now have a global network of millions of computers providing high-speed digital communications. Prior to the early 1990s university staff, government employees, and military personnel who were doing research, were the only people who used the Internet extensively. Now millions of users are surfing or browsing the Internet and even publishing their own home pages. There is no master plan, and no one person , company or government controls the Internet.
In 1989, Tim Berners-Lee at CERN, the European Laboratory for Particle Physics in Geneva, Switzerland developed a new set of standards for exchanging information on the Internet. The World Wide Web provided a way to link documents on any computer on any network. If you are in Minneapolis, MN you can click on a link on your computer screen and be connected to a computer in London , England. The release in 1992 of the WWW, based on public specifications, has allowed an explosive growth of this part of the Internet.
The WWW is a collection of documents located on different servers --- which could be a personal computer or a Super MainFrame computer. Each computer on the WWW is treated as being EQUAL to any other computer. These computers are linked by HYPERTEXT. That is, the user clicks on a “hot” spot in the document on his computer, then is transferred to the linked document on another computer located somewhere else in the world. Hypertext contains the invisible address of the computer where this linked to document resides. This “hot spot” usually appears underlined and in a different color then the surrounding text. When the POINTER ARROW moves over this “hot spot” it changes into a HAND with its INDEX FINGER extended. When this HAND symbol appears on your screen, you know that you have located a DOORWAY to another document. Double clicking on this LINK will take you to another webpage located somewhere in the world.
Special software, known as a browser, is needed to find and process these HYPERTEXT LINKS. The early browsers where text based. In 1993, several people at the University of Illinois at Champaign-Urbana came up with the first GRAPHIC web browser. They named it MOSIAC. Mosiac allowed users to transfer graphics AND text between the computers connected to the Internet. Since the release of this first graphical browser, the WWW has exploded in growth. The two most popular browsers today are Netscape Communicator and Microsoft Internet Explorer.
The information on the WEB resides on host computers know as WEB SERVERS. The computer on our desk, from which you acess information on the WWW, is known as the CLIENT.
The client computer, which is running a browser (for example Netscape), requests the linked document. The protocol or standard that enables the transfer of the request and the subsequent transfer of the linked document is HTTP – Hypertext Transfer Protocol. This is why, all website addresses BEGIN WITH the letters HTTP. For example,
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