chiptune

Short definition from Wiktionary

Noun

1. 1
   A piece of computer music in which the sounds are generated and mixed in realtime, common before the advent of mass storage for prerecorded sound.
2. 2
   A style of music that samples or emulates the audio capabilities of older sound chips, but ignores certain hardware or software limitations inherent to them; especially (demoscene) a tracker module simulating the sound of early 8-bit computers.