# REST APIs

## Introduction to API

API --> `Application Programming Interface` , is defined as a set of rules or protocols that are set to enable two software to communicate with each other. There are several types of API’s example `SOAP`, `XML-RPC` or `REST` This article will focus more on REST API.

Rest API stands for `REpresentational State Transfer`→ It is a set of functions (GET, POST, PUT ,Patch or Delete) that enables clients to perform `CRUD` operations that include `Create , Read, Update and Delete` resources in the data server.

There are Six REST API design principles.

* Uniform interface
    
* Stateless
    
* Client-server decoupling
    
* Cacheable
    
* Code on Demand
    
* Layered System
    

Rest API HTTP Methods

1. GET → Request Data from a server. The response contains all details requested.
    
2. POST→Create new resources on the server.
    
3. PUT→Update a Resource in the specified URL.
    
4. Patch->Update a Resource in specific fields or properties of an existing resource.
    
5. DELETE→Delete a Resource in the Specified URL.