Free x chat software for linux

XChat is an IRC (chat) program for Windows and UNIX (Linux/BSD) operating systems. I.R.C. is Internet Relay Chat, see http://irchelp.org for more information about IRC in general.
XChat runs on most BSD and POSIX compliant operating systems.
Main features:
- Full featured IRC client
- Fully customizable
- Tabbed window interface
- Small resource footprint
- 41 language translations
- encrypted connections using OpenSSL 0.9.8d
- native IPv6 support
- Perl, Python, Ruby and Tcl language interface plugins for scripting

AjaxChat is a simple, fast, and customizable chat server that uses Ajax to smoothly refresh and display the chat zone and the nickname zone.
AjaxChat project supports customized CSS stylesheets and plugins.
Online chat is a generic term for what are now mostly known as instant messaging applications-computer programs that enable two-way typing to connect users to each other.
However, there are net dating systems and other online services that do not use these applications to provide chat facilities, e.g., Delphi, often relying on HTTP-based protocols instead. Sometimes these are called a chat room or chat extending the physical metaphors of sites and magazines which many web services exploit.
Today there are many chat rooms, some incorporating instant messaging features without having to install additional chat software. These chatrooms often have friend finders built in.
Some of these systems also provide telephone voice mail access. These are usually known generically as just chat systems.
A chat log is a record of a chat. Sometimes this is put on the web.
The earliest online chat system widely used was probably the Unix talk facility. The earliest one in general use was likely the French Minitel. During the 1980s, online chat was made available on CompuServe and DDial servers, and later on GEnie. In 1988, Internet Relay Chat (IRC) protocol, an instant messaging tool, was developed and became the de-facto standard for online chat.
Enhancements:
- An optimized chat weight, a simplified initialization process, and simplified theme creation.

Claros Chat is finally ready. It is a web based (fully Ajax) instant messaging client which is capable of talking with the Jabber protocol. Claros Chat is well tested with Google Talk and it supports all major browsers such as Internet Explorer, Firefox, Safari, Mozilla.
The project has a minimalistic and an elegant user interface which looks much like a desktop application. Anyone interested in the application can test drive it at http://www.claros.org/chat.
Main features:
- Works with any Jabber server, including Google Talk.
- No setup needed on the client machine, works 100% within the browser, no plugins required.
- It is a 100% Ajax application, with a clean and nice user interface.
- Supports all major browsers.
- It can display user avatars including your own.
- Supports many of the emotions with MSN like smileys.
- All features such as changing status, changing status text, loading buddy list, adding/removing new buddy are all implemented.
- Can chat with as many users as you like.
- Users can set auto away at the preferences screen.
- Much words are useless, youve got to see it yourself, "it is one of the best looking and usefull open source instant messaging applications(or simply the best) in the world". See and believe for yourself. Just try the demo to see.(Login with your own Google username/password)
- You can start your own corporate chat network. Download a Jabber server from http://www.jabber.org and use Claros Chat to chat with your collegues.
- You can connect and chat with MSN, AOL, ICQ, Yahoo chat networks providing that you have your own Jabber server with a suitable gateway installed.
- It is open source and completely free software.

Voc is a stream-chat engine which is designed to work on high-loaded chat-servers. It is written in PHP, but uses Perl or C++ for Voc-daemon -- the special program to handle multiple user-connections. With Voc you can make a chat that will serve many conversations simultanously. And its html-based, so your chatters can use it from almost any browser.
The Voc-engine includes a lot of features so it will be interested not only for a big chat owners.
Whats so special about Voc-engine?
There are 2 classes of html-chats. Classic-type, with refreshing messages-window, And stream-type.
Refresh-type is known to everybody, so lets think about streams. What is the common way to introduce such functionality? Webmasters make cgi-script (PHP-script, jsp-srcpt, e.t.c) which checks for new messages every second (2,3...) and prints something to the client. Of course, you need one instance of the script for each client. Now calculate how many data-requests you need to process every second... At least two for each client -- get messages, get users-list.
Also dont forget about memory and CPU usage. For instance, if you have PHP-scripts and PHP is compiled as an Apache-module, be ready to spend 5 Mbytes of memory and 0.1-1% of CPU for each client (only for messages-window).Multiple it to number of users online.
Do you still want to use such scripts?
Is there any solutions? I guess, yes -- try Voodoo chat. It uses Perl- or C++-daemon which processes users-requests to a messages list. And you need just one daemon for all clients. This daemon takes approx. 10 Mbytes of memory for 100 users. CPU usage is also small (of course it depends on your CPU, i.e. for 100 users online it is 0.5% of Pentium 4 2.4 Ghz). Do you see the difference now?
Main features:
- Daemon-stream type (recommended)
- Classic-type (with refreshes)
- PHP-stream script (read text above and use this type only when you have less then 20 simultaneous visitors and cannot use daemon-type)
- JavaScript stream-emulation (refreshing hidden frame which just add text to the main message-window)
- Themes-support. You can use one of exisitng designes, or easily create your own
- rooms
- private messages
- ignoring
- you can enable to use bold, italic, underlined messages
- inline images
- personal info-page with photo for registered users
- avatars
- internal mini-mail system
- status (online/offline/not available/dont disturb)
- web-indicator (see example at the left)
- nick & string highlighing for personal messages
- anti-flood
- messages and ban/unban logging
- limits for maximum number of users and maximum number of users from one ip (anti-nick-flooding)
- graphical statistic, example
- admin-zone to manage the chat
- moderator-levels for registered users, so you can give someone permissions to ban/unban users, change rooms-info, edit/delete registered users

RobChat is an XML/HTTP chat script. It features multiple users, automatic updates without reloading, IE and Mozilla support, and a "whos online" window.

RobChat has the look and feel of a client-side chat client, but is written entirely in XML/HTTP, Javascript, and PHP.

MOHA Chat is a chat solution which comes with a intuitive Web client and can run on most shared hosts. MOHA Chat consumes fewer resources on the server side and is fast on the client side.

The project uses AJAX to retrieve the chat messages and user status. The client polls the server at regular intervals. It currently supports only one-to-one chatting with the Web client. The Web client encrypts messages using a key unique to the client when sending a message to the server and vice versa.

GtkChat is GTK+ based Vypress Chat TM clone. It uses GTK 2 and its Perl bindings. I tried to make UI simple and clean while maintaining same look as Vypress Chat.