Associated .MID software

Windows
MID file
Musical Instrument Digital Interface (MIDI) Sound File
The .mid file format is a Standard MIDI (Musical Instrument Digital Interface) file (SMF), which can also have the .midi extension.
These files contain music data, such as which notes are played, the key in which they're played and their length/volume. The format also supports MIDI controller information for instrument selection and effects.
As these files only contain play-back information, they do not contain any actual audio data.