MuseScore

MuseScore lets you notate and compose music easily with your keyboard, your mouse or a MIDI keyboard. You can print the beautifully engraved sheet music or save it as PDF or PNG. You can play your score, transpose it, and save it as audio or MIDI file. MuseScore also supports MusicXML to let you share your composition with other scorewriters. MuseScore is free and open source.

What is new in this release:

• New "Jazz Lead Sheet" template for great looking results right out of the box
• Enhanced MuseJazz font for use in titles and other text elements as well as in chord symbols
• Chord symbols can now be entered on beats that do not contain notes, allowing multiple chords to be entered in bars containing only a single note or rest
• Tab / Shift-Tab key during chord entry moves to next / previous measure
• New chord symbol style options, including triangle for major and circle with a slash for half-diminished
• New "Slash Notation Styles" plug-in available for download
• MuseScore community connection: twitter news and community contributed sheet music

Requirements:

Mac OS X 10.4 +