200 OK

The request succeeded. The body depends on the method: the resource for a GET, the result of the action for a POST.

Class
2xx Successful. The request was received, understood and accepted.
Registered
Yes, in the IANA HTTP status code registry.
Cacheable by default
Yes. A cache may store it without Cache-Control or Expires saying to.
References
RFC 9110 ยง15.3.1 · MDN

Every 2xx code

All HTTP status codes, in one table