说明：  http开发者手册，描述了http包文的规范等，对于从事底层Web开发有帮助。
(The HTTP Developer s Handbook is written specifically for Web developers. It begins by introducing the protocol and explaining it in a straightforward manner. It then illustrates how to leverage this information to improve applications. Extensive information and examples are given covering a wide variety of issues, such as state and session management, caching, SSL, software architecture, and application security.)