What are the type of error pages?

he type of error pages available are as follows:
Error 400: Bad Request
Error 401: Authorisation Required (when you create password-protected directory and there is an unauthorised entry attempt)
Error 403: Forbidden (when a person tries to access a forbidden page)
Error 404: Wrong page (when a person tries to access a file that does not exist on the server)
Error 500: Internal Server Error (when you try to install a CGI script but the script can not be compiled due to programming error)