“Error 404” (Page Not Found) – is a standard code of HTTP status that occurs when the server can’t find a document required by a user. Basically, this is a page that doesn’t exist.
But, in fact it’s not only one reason. In general we can single out even 3 reasons for this error:
1. The page you tried to access does not exist on this site.
2. The page was deleted by administration due to any reason.
3. The user has typed the URL incorrectly.