Chapter 12. HTTP requests

As mentioned in Chapter 9, communication on the World Wide Web happens over the HTTP protocol. This chapter describes how to use this protocol to make your client-side program talk to your web server.

The HTTP Protocol

A simple HTTP request might look like this:

GET /files/data.txt HTTP/1.1
Host: eloquentjavascript.net
User-Agent: My Imaginary Browser

This asks for the file files/data.txt from the server at eloquentjavascript.net. In addition, it specifies that this request uses version 1.1 of the HTTP protocol—version 1.0 is also still in use and works slightly differently. The Host and User-Agent lines are called headers. These follow a pattern: They start with a word that identifies the information they contain, followed ...

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