Behind every web transaction lies the Hypertext Transfer Protocol (HTTP) --- the language of web browsers and servers, of portals and search engines, of e-commerce and web services. Understanding HTTP is essential for practically all web-based programming, design, analysis, and administration. While the basics of HTTP are elegantly simple, the protocol's advanced features are notoriously confusing, because they knit together complex technologies and terminology from many disciplines. This book clearly explains HTTP and these interrelated core technologies, in twenty-one logica