KVIrc is a free portable IRC client.The program has support for mIRC-Codes for bold, underlined and colored font. KVIrc is able to connect to several servers at the same time (optional with SSL and/or IPv6).
KVIrc has its own script language named KVS for extensions, addons and scripts. Every channel, query and DCC Chat is encryptable with Blowfish or AES/Rijndael.
With the split window mode you can divide your channel window into 2, one for chat messages and one for "commands" like joins/parts/mode changes. The size of the windows is variable, so you can hide the command window.
The Socket spy feature helps developers and users to watch the raw communication between client and server to debug.
Similar applications:
MIRC, X-CHAT
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