Schemes or protocols instruct browsers/operating systems/mirc how to open (and interpret) URIs (links) that are often found on webpages, documentation and yes, IRC chat.
mIRC supports some standard protocols, http:// ftp:// and the optional irc:// . More protocols can be added in the registry (for example most systems also support telnet:// gopher:// news:// ) and configured to open the relevant programs. mIRC does not support this however, and only allows certain protocols to be clicked through (you can /run the unsupported protocols though).
If mIRC dynamically supported all protocol types, users would not have to request that so-and-so (eg callto:// and the now countless [well.. lots] of various p2p schemes) be added as a clickable link in mIRC, nor would users shoot them down as the protocol is too obscure/unofficial/naughty/whatever: If the protocol is supported by your system, it would be supported by mIRC.
I'm not sure of the technical limitations on this, mIRC could construct a list of supported protocols on startup and look for those in text. Would this slow down mIRC a lot? Would mIRCs handling of urls be broken (again)?
