A REST (Representational State Transfer) API is a powerful tool for building and connecting software applications over the internet. It allows different systems to communicate using HTTP requests to perform various actions on resources, like retrieving, creating, updating, or deleting data. REST is widely adopted due to its simplicity, scalability, and compatibility with web standards.
REST maintains a clear separation between the client (which requests resources) and the server (which provides those resources), which enhances scalability and flexibility. Each request from the client to the server must contain all the information needed to process the request. The server does not store any state about the client, meaning each request is independent and does not rely on previous interactions.
In REST APIs, resources are represented by unique URLs. For example, an API for managing a library might use URLs like /books to access books and /books/{id} to access a specific book.
REST APIs use a consistent, predictable structure in their endpoints. This typically includes using HTTP methods like:
- GET: Retrieve data
- POST: Create new data
- PUT or PATCH: Update existing data
- DELETE: Remove data
Common Use Cases for REST APIs
- Web and Mobile Applications: REST APIs are often used to power the backend of web and mobile apps, providing data and services to the user interface.
- Third-Party Integrations: Many companies use REST APIs to enable integration with other software systems, like payment processors or CRM tools.
- IoT Devices: REST APIs allow internet-connected devices to exchange data with remote servers, powering IoT applications.