404 Not Found
404 Not Found hardly needs an introduction. It’s by far the most seen
status by developers and non-developers alike.
404 is emitted when a
resource doesn’t exist, never existed or if the server doesn’t want a client
to know that a resource exist.
If the server knows the resource doesn’t and will never exist again,
410 Gone might be more appropriate.
404 response is incorrectly used as a successful response to
DELETE request. The logic behind this is that the resource no longer
exists after deleting, so the server should report this state.
HTTP/1.1 404 Not Found Content-Type: text/html
<h1>404 Not found</h1>
- RFC7231, Section 6.5.4 - 404 Not Found