What it's for
Port 194 is IRC's (Internet Relay Chat) officially IANA-registered port, though in practice almost every real-world IRC network and client uses the 6660–6669 range instead — a historical quirk where the "unofficial" convention won out over the formal registration. IRC itself is one of the oldest real-time text chat protocols still in active use, popular in open-source project communities and technical support channels.
Protocol basics
IRC runs over TCP for reliable, ordered delivery of chat messages within channels and direct messages between users. A client connects to a server, joins one or more channels, and sends/receives plaintext messages formatted according to the IRC protocol's simple command structure. Because port 194 requires elevated privileges on Unix-like systems (any port below 1024 does) while 6660+ doesn't, most server operators historically found it more convenient to run on the higher port range, cementing that as the de facto standard.