404 Not Found

Description
The HTTP 404 Not Found response status code indicates that the server cannot find the requested resource.
Links that lead to a 404 page are often called broken or dead links and can be subject to link rot.
A 404 status code only indicates that the resource is missing: not whether the absence is temporary or permanent.
If a resource is permanently removed, use the 410 Gone status instead.
See Also
Source: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/404