Commands always start with '.' or '/'.

Command	Meaning
/quit	This command will let you leave the chat again.
/me does something.	Sends an "action" or "emotion" to a channel.
/msg username text	Sends a text privately to the user with the given name
/join channel	Allows you to switch to another channel
/whois username	Requests additional information about the user with the given name
/who	Shows a list of all the users in the current channel
/who channelname	Shows a list of all the users in the given channel name
/list	Shows a list of all channels on the server
/users	Shows a list of all users on the server
/ignore username	Ignores the user with the given name, that means, you will not receive any more messages from that user
/unignore username	Stops ignoring the given user again
/ignorelist	Shows a list of all users you ignore
/oplist	Shows a list of temp and perm operators (ops) and marks the temp ops with brackets.

If you are operator in a channel, you have following additional commands:

Command	Meaning
/op username	Allows you to grant operator rights for somebody else
/deop username	Takes away the operator rights from a temporary operator
/kick username	Throws a user out from the channel
/mute username	Does not let that user speak anymore without him noticing it