IRCX (Internet Relay Chat eXtensions) is an extension to the IRC protocol, developed by Microsoft. IRCX defines ways to use SASL authentication to authenticate securely to the server, channel properties/metadata, multilingual support that can be queried using the enhanced "LISTX" command (to find a channel in your language), an additional user level (so there are three levels: owners, hosts, and voices), specific IRC operator levels, and full support for UTF-8 (in nicknames, channel names, and so on). IRCX is fully backwards compatible with IRC; the new features are downgraded to something a standard IRC client can see (and UTF-8 nicknames are converted to hexadecimal).