The Art of SEO, 2nd Edition

Glossary

301 status code

An HTTP status code returned by a web server indicating that content has been moved from one location to another. A 301 status code indicates a permanent server redirect, which is a signal that the original page no longer exists and that users and search engines should view the new page as the canonical version of that content.

302 status code

The 302 status code means that the document requested is “Found” but temporarily resides under a different URL. Since a permanent redirect has not been used, the client should continue to use the original requested URL for future requests.

400 status code

The 400 status code means a “Bad Request,” indicating that the server is not able to understand the document request due to malformed syntax.

401 status code

The 401 status code means “Unauthorized.” The server is requesting user authentication prior to fulfilling the document request.

403 status code

The 403 status code means “Forbidden.” The server understood the request, but is refusing to fulfill it. The webmaster may wish to alert the user as to why her request has been denied. If the organization does not wish to provide a reason, a 404 (Not Found) status code can be displayed instead.

404 status code

The 404 error message represents a document “Not Found.” This means that the client was able to communicate with the server, but the server could not find the requested document. Alternatively, the server could be configured to not fulfill the request and not provide a reason ...