Channels are a recent feature that's exclusive to the HTML5 version of Chatango. Initially, it had 8 channels and a mod channel, but it has now been stripped to just 2 channels and a mod channel.
A lot of users seem to use the channels as a decoration, 2nd Background, etc.
Contrary to popular opinion (and we are sorry to slap you for it):
Channels are for filtering topics and conversations.
Examples would be filtering out role play and off topic conversations from other conversations that have meaning.
They can also be used for filtering bots (if a bot allows you to force them to a certain channel).
Examples would be filtering the attack command (which will usually be spammed) on any bot.
Please note that this feature is in danger of being removed as alec believes he should never have made it a thing because too many people use it for the wrong reasons (and again we are sorry for slapping you for doing it).