Representational State Transfer. Representational State Transfer (REST) is a software architecture style consisting of guidelines and best practices for creating scalable web services. REST is a coordinated set of constraints applied to the design of components in a distributed hypermedia system that can lead to a more performant and maintainable architecture. REST has gained widespread acceptance across the Web as a simpler alternative to SOAP and WSDL-based Web services.
RESTful systems typically, but not always, communicate over the Hypertext Transfer Protocol with the same HTTP verbs (GET, POST, PUT, DELETE, etc.) used by web browsers to retrieve web pages and send data to remote servers. The REST architectural style was developed by W3C Technical Architecture Group (TAG) in parallel with HTTP 1.1, based on the existing design of HTTP 1.0. The World Wide Web represents the largest implementation of a system conforming to the REST architectural style.
Architectural properties Ajax and REST, Part 1. Ajax and REST, Part 2.