What is REST?

Representational state transfer (REST) is an architectural design pattern for APIs. APIs that follow this pattern are called REST APIs or RESTful APIs. REST sets certain standards between computer systems on the web that make it easier for systems to communicate with each other.

REST APIs are mainly characterized by their statelessness and the complete separation of client and server.

The REST pattern allows the client and the server to be implemented independently without the knowledge of the other entity. This means that code at either side can be modified without having to worry about the effect of the modification on the other side. As long as both sides agree on the format of communication between them, they can be kept modular.

Systems that follow the REST architectural style are stateless, i.e., one entity does not need to know the state of the other entity. This statelessness is achieved through the use of resources (the object or information that you need to store or send to other entities). Since operations on resources are fully standardized, the state/implementation of the other entity is not required.

Modularity and statelessness of REST APIs allow applications to be more reliable, perform better, and be more scalable.