A RESTful Web API (also called a RESTful Web Service) is a Web API implemented using the HTTP protocol and REST principles. It is a collection of resources, with four defined aspects:
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The PUT and DELETE methods are idempotent methods. The GET method is a safe method (or nullipotent), meaning that calling it produces no side-effects.
Unlike SOAP-based Web services, there is no standard for RESTful Web APIs. This is because REST is an architectural style, unlike SOAP, which is a protocol. Even though REST is not a standard, a RESTful implementation such as the IzoT REST API can use standards like HTTP, URI, and XML.
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