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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)

NNTP Status Responses and Response Codes 1 TCP/IP World Wide Web and Hypertext Overview and Concepts

So finally, we come to the Big Kahuna. J In my overview of file and message transfer protocols, I said that the World Wide Web was “almost certainly” the most important TCP/IP application. If anything, I was probably understating the case. The Web is not only quite clearly the most important TCP/IP application today, it is arguably the single most important application in the history of networking, and perhaps even computing as a whole.

Does this sound a little melodramatic? More than a little? Perhaps, but consider what the Web has done in the decade or so that it has been around. It has transformed not only how internetworks are used, but in many ways, has changed society itself. The Web put the Internet “on the map”, so to speak, moving it from the realm of technicians and academics and making it a big part of the mainstream world.

In this section I describe the World Wide Web in two subsections. The first discusses the Web and the concepts behind hypertext and hypertext documents in general terms. The second explains the operation of the all-important Hypertext Transfer Protocol (HTTP), the TCP/IP application layer protocol that makes the Web work.

NNTP Status Responses and Response Codes 1 TCP/IP World Wide Web and Hypertext Overview and Concepts