That is mIRC script. It's a language unique to mIRC (For now anyway *cough*). I'm assuming you're using mIRC.
You can use mIRC's Script Editor to paste code. Press
ALT+R to access it.
You could also search some of these mIRC-script-related sites to find ready-made addons if you prefer:
www.mirc.netwww.mircscripts.comwww.hawkee.comwww.mircscripts.orgRegards,
