Glossary: Web Performance

HTTP status codes

Also written: 200, 204, 304, 404, 413, 304 Not Modified, 200 OK, 204 No Content, 404 Not Found, 413 Content Too Large

Three-digit numbers a server sends to say how a request went: 200 OK (success), 204 No Content (success, nothing to send back), 304 Not Modified (use your cached copy), 404 Not Found (no such file) and 413 Content Too Large (body too big).