此文章转载自http://www.cnblogs.com/loveyakamoz/
HTTP教程一 : http://www.cnblogs.com/loveyakamoz/archive/2011/07/21/2112804.html
HTTP教程二 : http://www.cnblogs.com/loveyakamoz/archive/2011/07/21/2112832.html
HTTP教程三 : http://www.cnblogs.com/loveyakamoz/archive/2011/07/21/2113246.html cookie
HTTP教程四 : http://www.cnblogs.com/loveyakamoz/archive/2011/07/21/2113247.html 认证