Can you list the main HTTP status codes and their meanings?

Main HTTP status codes are divided into five categories:

• 1xx (Informational): for example, 100 Continue — the server has received the initial part of the request and the client can continue.
• 2xx (Success):
  • 200 OK — the request was successful.
  • 201 Created — the resource was successfully created.
• 3xx (Redirection):
  • 301 Moved Permanently — the resource has been permanently moved.
  • 302 Found — temporary redirection.
• 4xx (Client errors):
  • 400 Bad Request — invalid request.
  • 401 Unauthorized — authentication is required.
  • 403 Forbidden — access is denied.
  • 404 Not Found — resource not found.
• 5xx (Server errors):
  • 500 Internal Server Error — internal server error.
  • 503 Service Unavailable — service is unavailable.

These codes help the client understand the result of the request processing.