An old database-daemon registration; in practice a round number people pick for internal HTTP.
IANA assigns 800 to "mdbs-daemon" (registered under the older name mdbs_daemon), with no RFC, vendor documentation, or public implementation attached to it. Nothing in current use implements the registered protocol. What you actually find on 800 is usually something chosen by hand: an alternate HTTP listener, an admin console, or a proxy, because it is a memorable number just above the reserved 1-1023 boundary services.
Expose with care
Almost always an ad-hoc HTTP or admin service rather than the registered protocol; check what it is and whether it has authentication.
$ curl -sv -o /dev/null http://TARGET:800/Seen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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