HTTP Status Codes
In addition to HTTP methods, HTTP status codes of the response are particularly important, as they are used to identify the success or failure of an operation.
The Five Main Categories of Status Codes
The five main categories of status codes, identified by the first digit of the code, are:
1xx: Informational
The server informs the client that the request has been received and the process is ongoing.
2xx: Success
The operation was completed successfully. The server has received, processed, and accepted the client's input, and the user typically sees the requested web page or resource.
3xx: Redirection
The server receives the request, but further actions and steps are needed on the client side to complete it correctly, as there are forwards and redirects.