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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP File and Message Transfer Applications and Protocols (FTP, TFTP, Electronic Mail, USENET, HTTP/WWW, Gopher)                 9  TCP/IP World Wide Web (WWW, "The Web") and the Hypertext Transfer Protocol (HTTP)                      9  TCP/IP World Wide Web and Hypertext Overview and Concepts

TCP/IP World Wide Web and Hypertext Overview and Concepts 1 2 3 World Wide Web System Concepts and Components

At one point, I considered putting my section on the Web in a distinct location, separate from the discussion of other file and message transfer protocols. It didn’t “seem” at first like a message transfer protocol to me. But I realized that, boiled down, the Web really is just another way of storing information and then transferring it from one computer to another. A question immediately struck me: if this is the case, what was so special about the Web that caused it to become popular in a way that no prior messaging applications ever had?

There is no simple one-word answer to this question. However, if I had to give one anyway, it would be this: hypertext. Sure, applications like e-mail and Usenet allow users to send and receive information, and FTP lets a user access a set of files on a server. But what these methods lack is any way of easily representing the relationship between documents or providing a way of moving from one to another. Highly simplified, hypertext does exactly that: it allows the creator of a document to include links to related information either elsewhere in that document or in others. With the appropriate software, a user can easily move from one location to another.

Big deal? In fact, this is more important than it may initially seem. Without some way of linking documents together, they remain in unconnected “islands”. In some ways, hypertext-linked documents are to unlinked documents what networked computers are to those that are not networked. Consider the difference between this Guide and a hard-copy book; if I mention a topic in passing I can provide a link to it; a printed book cannot. Hopefully you’ve already discovered the advantages that this offers. J

TCP/IP World Wide Web and Hypertext Overview and Concepts 1 2 3 World Wide Web System Concepts and Components