IRC stands for Internet Relay Chat, a multi-user chat system allowing users to 'talk' in channels with many other users or privately to just one other user. A user connects to an IRC 'server' which may be connected to other IRC servers in a 'network.' The user can then talk in any channel on that network and to any user connected to the same network.

IRC was invented by Jarkko Oikarinen in 1988 as an improvement on the UNIX program 'talk', which allows users on networked UNIX systems to talk to each other in real time (when one user types a letter, it immediately appears on the other user's screen). It also resembles 'instant messaging' software such as ICQ, Yahoo! Instant Messenger and AIM (AOL Instant Messenger). The main difference is that instant messaging is generally used for private conversations with friends, while IRC channels are generally open to the public.

What is an IRC server?

An IRC server is a computer configured to allow connections from users, and to relay their messages to and from all the connected users as well as to any other servers in the same network. Each server runs a program called an IRCd (IRC daemon) which manages all the connections to the server and may be configured to block connections from certain IP addresses or users who have caused trouble in the past. There are many versions of the IRC server software including Bahamut¹.

Although you can get IRCd software which runs on Windows², all of the big networks use UNIX servers. The most popular operating system for the very big networks is BSD, whereas medium-sized networks use Linux. They explicitly ban Windows servers as they are considered too unreliable - IRC servers may run for months without rebooting.

The standard command to connect to a server is /server servername port, for example /server irc.dal.net 6667.

A server may be linked to other servers to form an IRC network, but it does not have to be - they can function quite well on their own.

What is an IRC network?

An IRC network is a collection of servers that are linked together. Every user connected to the network can see other users connected to the network no matter which server they are using.

The advantages of connecting a server to a network include giving users a server more local to them to allow for faster and more stable connections, and also increasing the number of users able to connect to a network. A single server may be able to take anything from a few hundred to many thousand users, and the largest networks have over 100,000 people using them at any one time. Netsplit.de provides usage statistics for almost all of the IRC networks in the world.

Who runs the network?

IRC networks are nearly always owned and run by volunteers, who tend to fall into the categories of admins and opers. Networks on the very large networks often have such high bandwidth demands that they are owned by companies but they still tend to have volunteer staff.

Admins

An admin (or server administrator) is the person who runs the server. Server admins set the rules for a server, as well as enforcing their policy. They often have a vote in network issues as well, such as deciding whether or not to link a new server.

Opers

An oper (or IRC operator, sometimes called an IRCop) is a person nominated by a server admin to assist in the running of the server. They are essentially janitors who ensure that the server keeps running smoothly for the users by removing disruptive users and answering questions.

An IRCop is listed in the server configuration file by an O line - the line which tells the server that they are an IRCop begins with O: followed by various details depending on the IRCd that is running the server.

Becoming an IRCop takes a lot of time and patience, as you can only ever get there by being invited by a server admin. You have to get to know them and show them that you are trustworthy, without ever implying that you are looking to acquire an O line (as 'oper-begging' is a cardinal crime only committed by lamers). If you don't already know other IRCops or a server admin, it may be almost impossible.

How do I connect to a IRC network?

First you need to decide which IRC network to connect to. You may hear of a particular channel through word of mouth or on a website or newsgroup devoted to an interest of yours, in which case the network should be mentioned. Otherwise, you may wish to consult Netsplit, which has an almost complete list of networks and enables you to search channel names and topics.

Once you have decided which network to connect to you need to select a server - you should look at either the network's website or Netsplit to find one. Often you can connect to a network at irc.networkname.com but there is no guarantee and you should check to ensure that you can connect. It's best to use a server close to you to ensure that you get a good connection.

Once you have selected a server, you then need a client to connect to it. There are literally thousands of IRC clients and millions of modifications³ available. Your client will come with instructions about how to connect to a server along with the commands it understands.

Which IRC client should I use?

The most popular Windows IRC client is called mIRC, written by Khaled Mardam-Bey in 1995 and updated frequently ever since. It is fairly simple but has a very powerful scripting language allowing you to customise it in any way you wish. There is a huge mIRC script repository at www.mircscripts.com but it is advised that you should not download any scripts until you are familiar with the basic program.

mIRC however is only available for Windows and a lot of technically competent people shun Windows in favour of the - in their opinion - much superior Linux, and so will need a client that works there. Again, there is a lot of choice, and almost all Linux distributions ship with an IRC client - in Mandrake it is called Ksirc. Jabber is an alternative client which can also be used to access most instant messaging systems.

The two most popular clients for Macintoshes are Snak and Ircle. For more information about these and other Macintosh IRC clients, see this Macintosh Chat Clients Page.

IRC channels

There are many channels on IRC, and you need to decide which one to talk in. Once you have connected to the network, you can type /list to get a complete list of channels, but this is a very bad thing to do on large networks, because the channel list can be so large that even with a cable modem it can take several minutes to transmit. Instead you should use /list *searchword* which will give you a list of all the channels containing your searchword.

Once you decide which channel you wish to join, then you can type /join #channelname to go there and start chatting!

Common IRC commands

IRC etiquette

Talking in BLOCK CAPITALS on IRC is considered to be shouting, and excessive use of colour or sound is also frowned upon. Flooding (sending more than about four lines at once to a channel or user), is also generally disapproved of, as is swearing. If you want to greet all your friends on the channel individually, use the /msg command so as not to clutter it up for everyone else. Also, do not run a program to greet people automatically. These rules apply to all channels, but many channels also have their own rules of etiquette, which may be linked to in the channel's topic or the message you get when you join.

IRC security

Do not give out personal details such as your full name, address or phone number on IRC, and remember that people online may not be who they say they are. If you are being harassed by another user, use the /ignore command.

IRC can be used to transfer files, which implies a risk of catching computer viruses. If you use Linux, you need not be concerned about this, as nobody has yet written a virus for Linux. Otherwise, you need to take precautions. Do not accept files from people you don't know unless the extension indicates that they are harmless. Plain text files (.txt) and pictures (.jpg) cannot contain viruses, but Word documents (.doc) can. Also check that your IRC client is not set up to accept files automatically.

If someone tells you to type a command, and you don't understand what it does, look it up with the /help command before you run it. In particular, the commands /run and /dll are used to access system functions and could mess up your computer. Also, never run a script unless you have read and understood it. Many scripts have been hacked to include commands that will compromise the security of your computer. Even if you got the script from a friend, the friend may not know how to tell whether it has been 'trojanned'.