RESTful Web services are very popular currently. REST (Representational State Transfer) is an
alternative to SOAP, XML-RPC etc., that provides simple, platform-neutral data exchange using the
HTTP transport. It can be integrated with HTTP more efficiently than SOAP based services.

RESTFul style can be good when web services are fully stateless, caching can be good for performance,
service consumer and producer have an understanding of the context, and bandwidth is important
and limited. Main advantages of REST web services are lightweight, human readable results and
easy to build.

RESTful systems map very closely to CRUD based-data operations. Using HTTP methods like PUT,
POST, GET, DELETE and a URI, the server takes action on the request. GET is used to query on a
resource. POST is used to create a new resource. PUT is used to update the resource. DELETE is
used to remove a resource.

Read more at http: //java.sun.com/developer/technicalArticles/WebServices/restful/