The glue between the frontend and backend

An Application Program Interface (API) is a set of defined functions that access data, perform operations, and decouple applications, e.g., a library.

Representational State Transfer (REST) is a software architecture for developing web services.

What exactly is RESTful programming?

Bringing these two concepts together, a REST API is a web service that has defined functions to retrieve data and perform operations. They decouple applications and works as a middle man between the frontend and the backend.

A Beginner’s Tutorial for Understanding RESTful API

They can be developed in most of the popular programming languages and are usually paired with a web framework. Some examples of this are Java and Spring, Javascript and Node/Express, and Python and Flask.

REST APIs live on the backend. This means they generally run on a remote server.

Generally, REST APIs use the HTTP protocol to communicate with the outside world. Each action will be assigned a URL path and accessed by a GET/POST/PUT/DELETE method. A great tool for working with APIs is Postman.

Postman is an API development app that presents an easy to read GUI for users to construct requests and read responses.

To create your own sample REST API please follow this exercise.