Representational State Transfer (REST) is an architectural style for building web services. It is based on a client-server model, where the client sends requests to the server and the server returns responses. REST defines a set of constraints and properties that make the communication between the client and the server consistent and scalable.
Some of the key principles of REST include the use of HTTP methods (such as GET, POST, PUT, and DELETE) to perform operations on resources, the use of URIs to identify resources, and the use of a stateless communication protocol, which means that each request from the client must contain all of the information necessary to understand the request, and cannot depend on information stored in the server.
REST is widely used for building APIs for web applications, and is a popular alternative to SOAP (Simple Object Access Protocol), which is another protocol for exchanging structured data over the internet. REST is often preferred over SOAP because it is simpler, more flexible, and less verbose.