What is the difference between REST methods?

REST (Representational State Transfer) is an architectural style for distributed systems, not a standard. However, it is commonly associated with using HTTP methods to interact with resources. The main HTTP methods used in RESTful APIs are GET, POST, PUT, PATCH, and DELETE. They are used to perform various operations on resources.

Method	Purpose	Idempotency	Safety	Example usage
GET	Retrieve resource data.	Yes	Yes	View user information.
POST	Create a new resource or send data for processing.	No	No	Register a new user.
PUT	Fully update an existing resource.	Yes	No	Update all user data.
PATCH	Partially update an existing resource.	No	No	Update only the user's email.
DELETE	Delete a resource.	Yes	No	Delete a user account.

Important differences:

• GET and DELETE are idempotent (multiple executions give the same result as a single one), while POST and PATCH are not. PUT is also idempotent.
• GET is safe (does not change the resource state), unlike the other methods.
• PUT is intended for complete replacement of a resource, while PATCH is for partial updates.

For example, working with the "user" resource (/users/{id}):

• GET /users/123 - get information about the user with ID 123.
• POST /users - create a new user (data in the request body).
• PUT /users/123 - fully update user 123's data (data in the request body).
• PATCH /users/123 - partially update user 123's data (e.g., only the email field, data in the request body).
• DELETE /users/123 - delete the user with ID 123.

The choice of method depends on the type of operation to be performed on the resource. Using the correct HTTP methods is key to creating understandable and predictable RESTful APIs.