Chapter 1This is the Title of the Book CHAPTER 1 Overview of HTTP The world’s web browsers, servers, and related web applications all talk to each other through HTTP, the Hypertext Transfer Protocol. HTTP is the common lan- guage of the modern global Internet. This chapter is a concise overview of HTTP. You’ll see how web applications use HTTP to communicate, and you’ll get a rough idea of how HTTP does its job. In particular, we talk about: • How web clients and servers communicate • Where resources (web content) come from • How web transactions work • The format of the messages used for HTTP communication • The underlying TCP network transport • The different variations of the HTTP protocol • Some of the many HTTP architectural components installed around the Internet We’ve got a lot of ground to cover, so let’s get started on our tour of HTTP.