A RESTful Web Service is a service whose interface and accessing mechanism are aligned with the REST principles . The URIs identify the resources. For example, a RESTful resource for a book can be identified as http://foo.org/book.
A resource for a book identified by ISBN could be http://foo.org/book/isbn/1234459. This shows a human-readable URI that is easy to understand and identify.
A client has enough metadata of a resource to modify or delete it as long as it is authorized to do so. To get a resource the client would send a HTTP GET
request. To update the resource the client would send a PUT
request. To delete a resource the client would send a DELETE
request. To create a new resource, and for arbitrary processing, the client sends a HTTP POST
request. The next section covers these verbs in more detail.