If you've spent any time around web development, you've probably heard the term REST API. But what exactly is it?

A REST API (Representational State Transfer Application Programming Interface) allows different software systems to communicate with each other over the internet using HTTP methods.

It's one of the most common ways for frontend applications to interact with a backend server.

Code Example

Here's how you might fetch data from a REST API using JavaScript:

JavaScript
// Using fetch to call a REST API
fetch("https://api.example.com/users")
  .then((response) => response.json())
  .then((data) => console.log(data));

The server responds with data (usually in JSON format), which you can use in your application.

Key Concepts

• Resources: Data or objects (like users, posts, etc.) the API manages.
• Endpoints: URLs that represent resources, e.g., /api/users.
• HTTP Methods: Define the type of action you want to perform:
  • GET: Retrieve data
  • POST: Create new data
  • PUT: Update existing data
  • DELETE: Remove data

Example API Structure

Let's say we're building a blog. The API might look like this:

• GET /posts - Fetch all blog posts
• GET /posts/1 - Fetch post with ID 1
• POST /posts - Create a new post
• PUT /posts/1 - Update post with ID 1
• DELETE /posts/1 - Delete post with ID 1

Why REST APIs Matter

• Separation of Concerns: Frontend and backend work independently.
• Scalability: Easy to manage and extend.
• Platform Independence: Any device or app can use the API.
• Data Standardization: JSON format makes it easy to parse and use.

Features

• Stateless: Each request is independent and contains all necessary info.
• Resource-Oriented: Everything is treated as a resource with a unique URL.
• Standard Methods: Uses HTTP verbs consistently.

Next Steps

Try creating a simple REST API using Express.js or connect to a public API like https://jsonplaceholder.typicode.com to experiment. Once you understand REST, you're one step closer to mastering backend development!