MIDI, MP3, and WAV: What Makes Them Different?

These three formats are often grouped together, but they do very different jobs.

A simple breakdown

WAV is uncompressed audio, so it sounds great but takes a lot of space.
MP3 is compressed audio designed for playback and casual listening.
MIDI is not audio at all. It is a set of instructions that tells an engine what notes to play.

For karaoke, MIDI is especially useful because it can change key and tempo without damaging the original sound.