MIDI (Musical Instrument Digital Interface) composition takes advantage of the MIDI interface to allow musical data files to be shared among various electronic instruments by using a standard list of commands and parameters known as General MIDI (GM). Because the musical is simply data and not actually recorded wave forms, (the data is essentially a series of "on" and "off" commands, along with numerical information) and is therefore maintained in a small file format. Several computer programs allow manipulation of the data so that composing for an entire orchestra is possible and can be reproduced by any electronic instrument that adheres to the GM standards. There are many websites that allow downloads of popular songs as well as classical music.

Along with the standard MIDI format, a popular variation is the .KAR format, a standard GM MIDI file with embedded song lyrics which, when played back using a compatible PC karaoke player, display the lyrics karaoke-style while playing the song. Although the MIDI karaoke format precludes the use of background vocals and harmonies, the incredibly small size of the file (in comparison to other "digital music" formats), the ease with which the files may be modified and edited, and the ever-increasing quality of midi instrumentation has ensured the continued popularity of the MIDI karaoke format.