The Demoscene orignates from the computersoftware pirate-scene in northern europe/scandinavia in the late 80s. Nowdays the "sceners" make multimeda demonstrations to show what your "demogroup" can do on the computer.
A demogroup consists of coders graphichsians and musicsians.
commodore64 music. All the sounds are generated from the SID-chip.
Modern chips has to be either a SID or a module (see module) using 4 channels, and only sinuswave-like sounds.
Nintendo 8bit music is chipmusic for instance.
Dude, this chipmusic r0x dah house. I know. Its sweet.