4xx status codes are HTTP response codes that indicate a client error, meaning that the request made by the user was not successfully processed by the server. These errors typically arise when a webpage cannot be found or accessed due to various reasons.
The most common 4xx code is 404 Not Found, which signifies that the requested resource does not exist on the server. This can occur if a page has been deleted, moved without proper redirection, or if there was an incorrect URL entered. Other notable 4xx codes include 403 Forbidden, indicating that access to the requested resource is denied; and 400 Bad Request, which suggests that the server could not understand the request due to malformed syntax.
