You can start talking in the channel when Snak displays the "You have joined
the channel" message.
All channel members see the normal messages that you send, but you can also
send messages that are only seen by a particular recipient. Those are called private
messages and are explained in chapter Private messages.
Busy IRC channels can be confusing because there are usually several threads
of conversation going on at the same time. Like at a party you will have people
gather in small clumps and talk about something. The difference is that unlike
a party you hear all the threads, all mixed together. It takes a little bit
of practice to keep the threads separated but IRC does have the advantage that
the text is preserved in your windows. That way you can scroll back and forth
in the conversation that streams into your computer until you get a handle on
what is going on.
You can turn on the Colorize the Nicks option in the Message
preferences in order to assign a particular color to each speaker. That
may make it easier to follow the threads.
When you join a channel you should probably wait in the background without jumping
into the fray until you know what the other members are talking about.
In addition to public and private messages that are basically conversational
you will see a third kind, called action messages that are used more for "environment".
You can use those messages to describe moods or opinions that are intended for
the whole channel. Action messages are issued by the /me command that is described
in the chapter on basic IRC commands.
The server to which you send your messages is responsible for passing them on
to other servers which in turn send it to the IRC clients of the other channel
members. Normally this happens almost instantaneously but sometimes you will experience
what is called "lag". Lag means that one of the servers between you
and the other channel members is overloaded and need to delay the messages.
When the delay clears up you will suddenly see a surge of messages in your window
and you will wonder what happened. Normally conversations in IRC are pretty much
real time but in a lagged situation a significant amount of time (10 seconds to
a minute or more) will pass before your messages reach the other members and vice
As mentioned above, the server you are connected to, is also connected to other
servers so that it can relay messages. Sometimes that connection goes down,
and if that happens it's as if the IRC world suddenly splits in two. Those people
connected directly to the server can continue as usual, but their messages aren't
going anywhere outside of the server. All the other channel members will suddenly
seem to disconnect en masse and you may even find yourself completely alone
in the channel. This phenomenon is called server splits or server desynchs.
The connection can go down due to malicious actions or simple overload. You
can try switching servers with the Cmd-E command to find a server on the other
side of the split, but the connection will eventually be restored. When that
happens there will be a stream of reconnects and everybody comes back.