HTTP 协议 的简单解释

At a glance, HTTP is a fairly simple, text-based protocol built on top of TCP/IP. Every HTTP session is initiated by establishing a TCP connection to the server, typically to port 80, and then issuing a request that outlines the requested URL. In response, the server returns the requested file and, in the most rudimentary use case, tears down the TCP connection immediately thereafter.

摘抄至：《The Tangled web（A Guide to Securing Modern Web Application）》