 A type 0 file contains the entire performance, merged onto a single track, while type 1 files may contain any number of tracks that are performed in synchrony.Type 2 files are rarely used and store multiple arrangements, with each arrangement having its own track and intended to be played in sequence.Microsoft Windows bundles SMFs together with Downloadable Sounds (DLS) in a Resource Interchange File Format (RIFF) wrapper, as RMID files with a codice_2 extension.