Sibelius!

MuseScore is a free music notation and composition software available for Linux, Windows and Mac.

Guitar Pro is first and foremost a program designed to edit tablatures for guitar, bass, and other fretted instruments from 4 to 8 strings.

Rosegarden is a well-rounded audio and MIDI sequencer, score editor, and general-purpose music composition and editing environment.

GNU LilyPond is a computer program for music engraving. One of LilyPonds major goals is to produce scores that are engraved with traditional layout rules, reflecting the era when scores were engraved by hand. It uses a simple text notation for music input, which LilyPond interprets and processes in a series of stages. In the final stage, music notation is output to PDF (via PostScript) or other graphical formats, such as SVG or PNG. LilyPond also has the facility to generate MIDI files that correspond to the music notation output. »

Frescobaldi is a LilyPond sheet music text editor. It aims to be powerful, yet lightweight and easy to use. Frescobaldi is Free Software, freely available under the General Public License.

Anvil Studio is a free Windows 7/Vista/XP/2000/98 program designed for people who want to: -- record music with MIDI and Audio equipment, -- compose music for MIDI and Audio equipment, -- sequence music with MIDI equipment, or -- play with music using a computer and sound card.

Finale is proprietary scorewriting software developed by MakeMusic, Inc. It displays music primarily in music notation and allows for multiple tracks and very specific tweaking of instrument sounds for each track.

GNU Denemo is a music notation editor that lets you rapidly enter notation for typesetting via the LilyPond music engraver. You can compose, transcribe, arrange, listen to the music and much more.

Impro-Visor (short for “Improvisation Advisor”) is a music notation program designed to help jazz musicians compose and hear solos similar to ones that might be improvised. The objective is to improve understanding of solo construction and tune chord changes. There are other, secondary, things it can do, such as improvise on its own. It has also been used for transcription. Because rhythm-section (e.g. piano, bass, drums) accompaniment is automatically generated from chords, Impro-Visor can be used as a play-along device. Now having a wider array of accompaniment styles, its use is not limited to jazz. »

Music21 is a Python-based toolkit for computer-aided musicology.Applications of this toolkit include computational musicology, music informations, musical example extraction and generation, music notation editing and scripting, and a wide variety of approaches to composition, both algorithmic and directly specified.

Canorus is a free cross-platform music score editor. It supports an unlimited number and length of staffs, polyphony, a MIDI playback of notes, chord markings, lyrics, import/export filters to formats like MIDI, MusicXML, ABC Music, MusiXTeX and LilyPond.

ABCJ is a pure-Java editor, player and librarian for music files stored using Chris Walshaw's ABC notation.

StaffPad is a brand new class of notation app, designed to take advantage of the advanced pen and touch input found on Microsoft Surface* and other compatible Windows 8.1 devices. As you write notation using the pen, StaffPad recognises your handwritten music and converts it into a beautifully typeset score which you can further edit, playback, print and share. StaffPad combines the best of working on paper with the best of working digitally, evolving the same process that's been used for hundreds of years to write countless masterpieces. Natural pen input, detailed orchestral playback and powerful score editing features mean that StaffPad is perfect for professionals, and easy for beginners. For the first time, an entire orchestra is available at the tip of your pen. Getting StaffPad is easy - it's available exclusively on the Windows Store. What will your masterpiece be? »

Next-generation 64-bit scoring software for OS X and Windows, designed by musicians for musicians Beautiful engraved output with unrivaled attention to detail Flexible note input and powerful editing, including ability to insert and change duration of existing notes Streamlined, single window interface puts every tool at your fingertips