Definition of Internet Relay Chat (IRC) in Network Encyclopedia.
What is Internet Relay Chat (IRC)?
Internet Relay Chat is a technology for using the Internet to send real-time, text-based messages. Internet Relay Chat (IRC) is defined in Request for Comments (RFC) 1459.
How IRC works
IRC is a client/server technology in which users employ IRC client software to connect to an IRC server or hub. Clients can then connect to an existing chat group (also called chat room or channel) and type messages to other users currently in that group. Chat groups are identified using a pound sign (#) prefix. Messages are transmitted in real-time and can appear character by character on the recipients’ client software if the person sending the message types slowly enough.
Depending on how the chat server is configured, users might be able to create their own chat rooms and hold private discussions. Some chat servers require that you register once to obtain a unique nickname, while others allow you to select a nickname for the current session only. Some Web sites also offer Web-based interfaces to their chat servers.
Microsoft Exchange Server version 5.5 includes an IRC-based chat server that you can use to set up public or private IRC sites.
Basic Internet Relay Chat commands
Every IRC client has an input area where you can type what you want to say or issue IRC commands. You issue IRC commands by typing on a new line something beginning with a / (forward slash) character. Anything that does not begin with a / is assumed to be a message you are typing to someone or some channel. In the following I will describe the more common commands used in everyday IRC life. Commands you are supposed to type will be shown in
**red**, while text which you will see in response will be shown in
In addition, the graphical clients such as mIRC or Ircle allow you to use a mouse to point and click your way around IRC, so that you don’t have to type many of these commands manually. You should still learn the commands properly because often they are the only way to specify precisely what you want done, and also they are often faster and easier than navigating through the labyrinth of buttons, menus, and dialogs that are supposed to make your life easier.
/HELP [optional command name]
The first and most useful command is the on-line help built into all good IRC clients just by typing
/help where you normally type to chat. This should bring up a list of all commands. You can also get specific help for a command, such as
/help who for the /who command.
You can get a quick introduction to IRC built into your client. mIRC users type
/ircintro while ircII users type
/help intro or
If you are not sure about the spelling of a mIRC command, just type in the first few letters. The help window, which shows commands arranged alphabetically, will open to approximately the right place so that you can choose to learn about a specific command.
If you are not sure about the spelling of an ircII command, type the first few letters and press the ESCape key twice. ircII will give you a listing of COMMANDS and ALIASes that start with that prefix. Don’t forget the “/irchelp/” in front of the command, though.
For example, you type the following:
You get as a response the following (this is just an example. Your screen may show more or less aliases or commands):
*** Commands: *** WAIT WALLOPS WHILE WHO *** WHOIS WHOWAS *** Aliases: *** W WA WH WI
Each server is known by a “hostname” such as irc.ais.net, us.undernet.org, irc.dal.net, or irc.webbernet.net, which are sample servers for the networks EFnet, Undernet, DALnet, and IRCnet, respectfully. Just specify the hostname to connect or switch to that server. For example:
You then see the following messages indicating your client has successfully connected to that server.
*** Looking up your hostname... *** Found your hostname, cached *** Checking Ident *** Got Ident response *** Welcome to EFNet IRC - the Internet Relay Chat Network foo *** Your host is irc.psinet.com, running version 2.8/hybrid-5.3 [remaining server messages truncated]
Change the nickname by which you are known. Nicknames are usually limited to 9 characters. For example, if your default nick was “foo” and you want to change it to “YourNick”:
/NICK YourNick *** foo is now known as YourNick
Lists IRC channels, number of users, and topic for each. This is how you find places to go meet people and chat.
/LIST *** Channel Users Topic *** #test 1 this is a test channel *** #IRChelp 18 Ask questions on the channel or see www.irchelp.org [remainder of list not shown]
If you’re on a big network, this list may be very long, up to many thousands of channels! It may even cause you to flood yourself off so that you get disconnected from the server. If that happens, try using different servers on that network, or instead use the searchable EFnet channel list web page which is updated hourly or the less frequently updated but more comprehensive Liszt channel list.
You can also search for specific keywords by using
/LIST keyword in mIRC, or
/LIST *keyword* in ircII. Note this may or may not be any faster or safer than a full list depending on the network. On networks like EFnet and IRCnet, for example, your client gets the full list first and then does the filtering internally before displaying matches to you. On Undernet, the server filters the list and sends only the matches to you, which can be much faster if you’re on a slow modem.
Shows the nicknames of all users on that channel. While theoretically this is supposed to work whether or not you are on that channel, in practice most people these days are set to be “invisible” and thus do not show up on such queries unless you are in the same channel already.
/NAMES #demo Pub: #demo @YourNick +buddy DeepMpact @FunGuy PrettyGrl
The “@” symbols show that YourNick and FunGuy are “channel ops”, and that buddy has been given a “voice”. These terms will be described in more detail in the channel modes section later.
Shows information about the nick specified.
/WHOIS buddy *** buddy is firstname.lastname@example.org (Think different.) *** on channels: @#demo #test123 *** on irc via server irc.psinet.com (PSI Net EFNet IRC Server)
The “email@example.com” looks like an email address but actually abcd is buddy’s identifying “username” on dialup-6.provider.com, which is the “hostname” of the computer buddy is using for IRC. One cannot arbitrarily change the hostname, because it is the computer’s address on the Internet, and it is required in order for the IRC server to communicate with one’s computer properly. Next, in the parentheses, buddy shows a personal message instead of the real name which is supposed to go there.
The second line shows he is on the “public” channels #demo and #test123, and the @ symbol means he is an operator on #demo. It doesn’t show other, “secret” channels he might be on. Finally, the third line shows which Internet Relay Chat server he is using.
Leave a message explaining that you are not currently paying attention to IRC.
/AWAY getting coffee, be back in 5 mins You have been marked as being away
If your friend does /whois YourNick now, they will get the 3 lines as described in the /whois section above, plus a final line saying:
*** YourNick is away: getting coffee, be back in 5 mins
/AWAY without any additional argument will remove the away message.
/AWAY You are no longer marked as being away (or something to that effect)
/QUIT [optional farewell message]
Exits IRC (also leaves any channels you may be on).
/QUIT hasta la vista, baby! *** Signoff: YourNick (hasta la vista, baby!)
Channel operators or “ops” have absolute power over their channel, including the right to decide who gets to come in, who must leave, who may talk, etc. When you first start out, it’s best to chat on other people’s channels and heed their rules, or else you may find yourself kicked out. If that happens and you cannot settle your differences with the ops, just go to another channel.
At some point, you will probably want to try your hand at being a channel op, either by creating your own new channel or by gaining the trust of the ops on an existing channel. You need to know a whole different set of commands. With this power comes the sometimes frustrating responsibility of maintaining the channel against intentional abuse as well as the usual Internet Relay Chat mishaps.
Some networks such as Undernet and DALnet support channel registration, whereby you can “reserve” a channel. The advantage is that you are assured control over the channel as long as you show up once in a while, the disadvantage is that many popular channel names are probably already registered by others.
Two of the largest nets EFnet and IRCnet do not support channel registration (or any other services). On these nets, there is no way to ensure you will always control a channel. Some channels try hard with all sorts of bots (which are explicitly banned by most servers) and protective scripts, but it’s really just a matter of time before somebody with the right combination of lameness and knowledge comes along and takes over the channel.
mIRC – The most popular Internet Relay Chat Software
mIRC is a popular Internet Relay Chat client used by individuals and organizations to communicate, share, play and work with each other on IRC networks around the world.
You can still download and install mIRC. The latest version is mIRC v7.57 for Windows XP/Vista/7/8/10. Download mIRC