music21 - Music21 is a Python-based toolkit for computer-aided musicology.
MuseScore.org - Create, play back and print beautiful sheet music with free and easy to use music notation software MuseScore. For Windows, Mac and Linux.
Harmony Assistant - Harmony Assistant is an unbeatable software for computer-assisted music composition and editing.
Guitar Pro 7 - Create, play and share your tabs
tonica fugata - Composing it for you... Automatic three and four-part composition (styles: J.S.
Finale - Finale, the world standard for music notation software, lets you compose, arrange, notate, and print engraver-quality sheet music.