LilyPond

LilyPond is a computer program and file format for music engraving.

One of LilyPond’s major goals is to produce scores that are engraved with traditional layout rules, reflecting the era when scores were engraved by hand.

LilyPond is cross-platform, and is available for several common operating systems; released under the terms of the GNU General Public License, LilyPond is free software and part of the GNU Project.