Architectural Styles and the Design of Network-based Software Architectures (http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm http://www.ics.uci.edu/~

Architectural Styles and the Design of Network-based Software Architectures (http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm) is a very readable dissertation on Web architecture. It is the definitive source on REST. Architecture of the World Wide Web (http://www.w3.org/TR/webarch/ http://www.w3.org/TR/webarch/) is also worth a visit.