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Colloquy is an open-sourceIRC, SILC and ICB client for Mac OS X. It uses its own chat core that is also included as part of the ChatKit project, though in the past it used Irssi as its IRC protocol engine. Its developers' goal is to offer a robust IRC, SILC and ICB experience to users while blending seamlessly with the look and feel of other Mac OS X applications. To this end, Colloquy provides a user interface that is consistent with Apple's Human interface guidelines in addition to traditional IRC command-line controls. Colloquy also has comprehensive support for scripting and can be automated using Applescript. Colloquy 2.1 is the last supported version of Colloquy for OS X v 10.3.
Features
A popular effect of IRC Clients is the colors they support. Colloquy's main colors are: White, Black, Navy, Forest, Red, Maroon, Purple, Orange, Yellow, Green, Teal, Cyan, Blue, Magenta, Grey, and Ash. Scripting is another popular feature, and those who understand the scripting will find it easy to use AppleScript to attach scripts to Colloquy. Additional scripts can be written with languages such as F-Script, Javascript, Objective-C, Python, and Ruby. You can also see changes that are not visible with IRC, such as mode changes, ban sets, etc. The namelists for channels can be shown at the same time, so you don't have to switch channels to see who is on them. You can also underline words, use italics, bold, and outline.
Plugins and customizability
Colloquy supports customizable message views called "styles" using XSLT and Apple's WebKit renderer.
These act like themes, completely altering the way the application displays chat sessions. The software also supports a wide array of plugins that enable customization of the application and integration with other aspects of the Mac OS X environment.