LilyPond is an automated engraving system. It formats music beautifully and automatically, and has a friendly syntax for its input files. It is Free Software (‘open source’).

MuseScore is a free cross platform WYSIWYG music notation program, licenced under GNU GPL. Some highlights include (a) WYSIWYG, notes are entered on a "virtual note sheet," (b) Unlimited number of staves, (c) Up to four voices per staff, (d) Easy and fas