Here are some of the most common HTTP status codes and their meanings:

• 1xx – Informational: These status codes indicate that the request has been received and is being processed.
  • 100 Continue: The server has received the request headers and is waiting for the request body.
  • 101 Switching Protocols: The server has switched to a different protocol, such as HTTP/2.
• 2xx – Success: These status codes indicate that the request has been successfully received, understood, and accepted.
  • 200 OK: The request has been successfully completed.
  • 201 Created: The request has been fulfilled and a new resource has been created.
  • 202 Accepted: The request has been accepted for processing, but the processing has not been completed yet.
• 3xx – Redirection: These status codes indicate that further action needs to be taken in order to complete the request.
  • 301 Moved Permanently: The requested resource has been moved permanently to a new location.
  • 302 Found: The requested resource has been temporarily moved to a new location.
  • 304 Not Modified: The requested resource has not been modified since the last time it was requested.
• 4xx – Client Error: These status codes indicate that the request contains bad syntax or cannot be fulfilled.
  • 400 Bad Request: The request cannot be understood by the server.
  • 401 Unauthorized: The request requires authentication.
  • 404 Not Found: The requested resource could not be found.
• 5xx – Server Error: These status codes indicate that the server has encountered an error while processing the request.
  • 500 Internal Server Error: An unexpected error has occurred on the server.
  • 503 Service Unavailable: The server is temporarily unavailable.
  • 504 Gateway Timeout: The server did not receive a timely response from another server.

There are many other HTTP status codes, but these are some of the most common ones. You can find a complete list of HTTP status codes here: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status