[REST API is one of the bases for communication between systems on the web. It allows applications, websites and services to exchange data in a standardized way. For those just starting out, understanding REST is essential, because it is present in almost every digital product.
This guide explains what REST API is and provides a practical step-by-step guide to understand how it works.
What is a REST API
[REST API2 is an architectural style for communicating between systems using HTTP. It is based on HTTP resources and methods such as:
- GET (search)
- POST (create)
- PUT (update)
- DELETE (remove)
REST is simple and widely used.
Why REST is so used
- Easy to understand.
- Works in any language.
- Scales well.
- Uses web standards.
Therefore, REST is the most common standard for APIs.
Step by step in practice
Step 1: Define resource
Example: /users
Step 2: Define operations
- GET /users
- POST /users
- GET /users/{id}
- PUT /users/{id}
- DELETE /users/{id}
Step 3: Return JSON
REST APIs generally respond in JSON. Example:
{ "id": 1, "name": "Joao" }
Step 4: Handle errors
Return appropriate HTTP codes:
- 200 (success)
- 400 (request error)
- 404 (not found)
- 500 (internal error)
Real cases
- Mobile apps consuming data from a backend.
- Websites pulling product catalogues.
- Integrations with external services.
Quick checklist
- Well-defined resources?
- Correct HTTP methods?
- Responses in JSON?
- Consistent error codes?
If something is missing, the API can get confused.
Conclusion
REST API is the most used standard for integrations. With the step-by-step guide in this guide, you understand how it works and how to apply it in practice.
Use this roadmap as a foundation for creating simple, efficient APIs.