Representational State Transfer (REST) is an architectural style for creating web services. REST is neither language- nor platform-dependent; different clients like mobile apps, browsers, and other services can communicate with each other. RESTful services can be scaled easily to fulfill increased demand.

REST is not a standard but a set of constraints, defined by Roy Fielding. The constraints are as follows:

• Stateless: The server shouldn’t hold any information about the client state.
• Client-server independence: The client and server should act independently. The server should not send any information without a request from the client.
• Cacheable: Many clients often request the same resources; therefore, caching should be applied to resources in order to improve performance.
• Uniform interface: Requests from different clients should look the same. Clients may include, for example, a browser, a Java application, and a mobile application...