CGI:IRC allows you to use Internet Relay Chat from a web browser without having to use Java.
It supports most IRC commands you could need in daily use. As well as providing access controls and other features.
Once you have logged into a server and joined a channel, you can use almost all of the commands, and say things in the channel. As it supports multiple channels you can select the channel you want to talk to in the far left box at the bottom and then type the text into the text box and click say.

Commands begin with / and are used for many purposes. This is a table of all the commands plus a short description of what they do
CommandInfo
/msg <nick> textSend text to nick as a private message
/whois <nick>Shows information about <nick>
/whowas <nick>Shows information about who <nick> was
/who #channellists the users in a channel
/listlists all the channels (use with care)
/partleaves the channel
/join #channeljoins #channel
/nick <newnick>changes your nick to newnick
/me textdoes an action of text on the channel (eg. /me throws somebody out of the window)
/quitleaves irc
/namesshorter form of /who
/ctcp
/quote
Channel Operator Only Commands
/mode
/kick
/topic
/invite
/op

It supports the use of colours and bold fonts by typing %Btext in bold%B, for text in bold and %C2,7colour text!%C. The colours uses standard mIRC colour codes and supports text with a background and without (miss out the ,7 bit for no background). Here is a list of all the colours:
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