Understanding HTTP Response Status Code – 404 : Not Found

The infamous 404 error is a HTTP response status code, also more commonly known as a page not found error, the code is reported when a requested website page cannot be physically found or located on the server, the error indicates that a connection to the server was successful and a two way communication channel between the server and the client is initiated and established, however the page requested is physically not available on the server.

Another similar error I recently discovered is a “410: Gone”, which indicates that the requested page has been intentionally removed and no longer available and will not be available again. Upon receiving a 410 the client should not request this resource again and search engines should remove the resource from their indexes.

Custom 404 error pages:

Web servers can usually be configured to display customised 404 error pages, so page is branded to look like the website template, and can provide redirect or links to the homepage and or other relevant pages, an easy way to implement custom 404 error pages, if your server does not support friendly 404 errors, then adding the following line of code to the .htaccess file will redirect the browser to a file called “missing.php”

ErrorDocument 404 /missing.php

Some Popular SEO Related HTTP response status codes

1xx Informational – Request received, continuing process.

100 Continue

2xx Success – The action was successfully received, understood, and accepted.

200 OK

3xx Redirection – The client must take additional action to complete the request.

300 Multiple Choices
301 Moved Permanently
302 Moved Temporarily
304 Not Modified
307 Temporary Redirect

4xx Client Error – The request contains bad syntax or cannot be fulfilled.

400 Bad Request
401 Unauthorized
403 Forbidden
404 Not Found
408 Request Timeout
410 Gone
413 Request Entity Too Large
414 Request-URI Too Long
418 I’m a teapot

5xx Server Error – The server failed to fulfil an apparently valid request.

500 Internal Server Error

SEO Advisor
Vipul