A channel is the fundamental means of communication, in a recognized IRC session. By using the command /list [#string] [-min #] [-max #], you can see all the channels in a server, [#string], being for the entire or part of the name and [#min] / [#max], meant for number of users in the channel.

The members can connect to various channels of their choice by using specific commands and then send text messages or files through it. The message is also sent to all the users in the same channel .Channels which are available on the entire IRC network can be accessed through "#" and the ones at local level by "&". Remaining channel which are included in IRC network are without mode for e.g "+"and in form of timestamped channels, that may be available at non-time stamped networks.

Users as well as channels, have there own modes which can be in form of some kind of switches or element linked to them. Single letters are used to abbreviate the modes which are easy to merge together when the connection begins. The 'I' command is commonly used to hide or land up in an invisible form. There are quite a many voice channels as well which can be used by the command 'm' that means "Moderated channels". An abuse control feature is also available by using the commands "k" which requires the user to enter a password to access a particular channel or in case invite somebody to his/her channel.

• Type A accepts an argument to add/remove values from a list (such as 'b'),
• Type B accepts an argument that is used when turning the mode 'on' and 'off' (such as 'k'),
• Type C accepts an argument only when the mode is turned 'on' (such as 'l'),
• Type D which accepts no arguments and is simply a Boolean flag (such as 'm', 'n', and't'),
• Type E (usually called 'class' or 'prefix' modes) that give/takes a opportunity from a user on a channel (such as 'o').

Four of the above channelmodes will accept an argument.