HTTP methods define the operation that a client wants to perform on a resource.

The most commonly used methods in REST API development are GET, POST, PUT, PATCH and DELETE.

GET retrieves information from the server.

Example:

GET /api/users

POST creates a new resource.

Example:

POST /api/users

PUT replaces an existing resource with a new representation.

Example:

PUT /api/users/123

PATCH partially updates an existing resource.

Example:

PATCH /api/users/123

DELETE removes a resource.

Example:

DELETE /api/users/123

Understanding the difference between PUT and PATCH is particularly important.

Suppose a user document contains:

{
  "name": "John",
  "email": "john@example.com",
  "age": 25
}

If you use PUT, the request generally provides the complete replacement representation.

If you use PATCH, you can update only the age:

{
  "age": 26
}

HTTP methods also have different safety and idempotency properties. GET is safe and idempotent. PUT and DELETE are idempotent by HTTP semantics. POST is generally neither safe nor inherently idempotent.