RESTful API (Representational State Transfer API)

A RESTful API (Representational State Transfer API) is a web service that follows REST (Representational State Transfer) principles, allowing communication between client and server over HTTP. It is widely used in modern web applications for exchanging data between frontend and backend systems.

RESTful APIs are a fundamental concept in web integration because they enable different applications, systems, or services to communicate with each other over the internet.

Why is RESTful API a Web Integration Concept?

1. Standard Communication:

   • RESTful APIs provide a standardized way for web applications to send and receive data over HTTP.

2. Separation of Frontend & Backend:

   • Modern web applications (like React, Angular, or Vue.js) use RESTful APIs to communicate with backend services (built in Node.js, PHP, Python, etc.).

3. Interoperability:

   • REST APIs allow different systems (mobile apps, web apps, databases, cloud services) to work together seamlessly.

4. Common Use Cases in Web Integration:

   • Fetching user data from a database
   • Authenticating users (OAuth, JWT)
   • Connecting with third-party services (Payment APIs, Google Maps API, etc.)
   • Uploading and retrieving files (images, documents)

5. Lightweight & Scalable:

   • Due to its stateless nature, RESTful APIs are easy to scale and optimize for high-performance applications.

Key Characteristics of RESTful APIs:

1. Stateless:

   • Each request from a client to a server must contain all necessary information, and the server does not store session state.

2. Client-Server Architecture:

   • The client (frontend) and server (backend) are separate, and they communicate via API calls.

3. Uniform Interface:

   • Uses standard HTTP methods like:
     • GET (Retrieve data)
     • POST (Create new data)
     • PUT (Update existing data)
     • DELETE (Remove data)

4. Resource-Based:

   • Data is treated as resources identified by URLs (e.g., /users, /products/1).

5. JSON or XML Format:

   • Typically, data is exchanged in JSON format (lightweight and human-readable).