mIRC is an Internet Relay Chat (IRC) client coded for Windows. It is the most popular Windows IRC client, and it's probably the most popular IRC client in the world. This might change soon though because so many people are moving away from Windows. Also, you can now get IRC clients built into your web browser, which users may find more convenient.
Khaled Mardam-Bey originally developed mIRC in 1995 to replace WinIRC. It has been consistently popular, and it's currently in version 6.35 (for Windows Vista). It's been downloaded over 20 million times. mIRC is free, but if you don't register it after 30 days it will start bugging you with pop-up prompts. Registering costs you $20.
It has an integrated scripting language, so that you can make changes to the functioning of the program yourself. It has a built in file server, making it easy to share files. It has many minor features that make it easy to use, and more are added every version. Although it is not open source, and all development is done by Khaled Mardam-Bey, he often adds features based on user requests and the scripting language allows users to modify the program to meet their needs. A computer savvy user can modify mIRC to be used as an IRC bot, a media player, or a web HTML parser.
No-one knows what the m stands for. Khaled Mardam-Bey says it might stand for mu, or it might just have sounded cool when he first wrote it. mIRC is often pronounced Mirk.
You can download mIRC here. http://www.mirc.com/get.html.
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