Irssi is a terminal based IRC client for UNIX systems. It also supports SILC and ICB protocols via plugins.

Greatest features
You might be wondering what makes Irssi such an easy and comfortable client to use:

Though I use Pidgin (formerly called Gaim) as my primary Internet Relay Chat client, I also installed Irssi, a text-mode IRC client. Why? --Because I use it to easily record an IRC channel's chat activity. How? --Here's how to do it:

Irssi is a popular IRC client. Its a very popular client for small window managers like fluxbox. This short howto will walk you though the steps for setting up a jail that only has a few commands in it and will help create a much safer IRC enviroment for you.

XChat is a GTK client for IRC, available on both Linux and Windows. It is one of the most popular and feature-rich IRC clients on the Linux platform, together with Konversation and KVirc. Of course, there are very good clients like Irssi too, but I'm talking only about graphical clients here.

In this article I will outline how to configure your IRC client to connect to the Freenode IRC network using SSL client encryption. This article includes instructions for Irssi, Empathy and Pidgin.

Anyone that has been reading these tips for any length of time knows that I am a command-line guy. It’s faster, more efficient, and more powerful. Sure, a nice GUI is great to look at, but to really get things done, give me the CLI any day. Even to this day I still use a text-mode e-mail client (Mutt) and text-mode IRC client (Irssi).

Internet Relay Chat (IRC) is a form of real-time Internet text messaging (chat) or synchronous conferencing. It is mainly designed for group communication in discussion forums, called channels, but also allows one-to-one communication via private message as well as chat and data transfers via Direct Client-to-Client.

Finch is a TUI (text user interface) IM client for Linux which uses libpurple, the same library on which the GNOME IM client Pidgin is based on. Usually, if you have Pidgin installed, you should have Finch too, unless Pidgin was compiled with the text interface option disabled.

Evilwm folks, you will love it. A twitter desktop client that is completely controlled from Terminal. Twidge is a command line twitter desktop client for Linux. It's feature rich and obviously easy to use.