GarageBand is a handy application for creating, editing, and just plain having fun with music. GarageBand works well with MIDI instruments, but if you don't have a MIDI keyboard, you can turn your Mac keyboard into a virtual musical instrument.
Click GarageBand's Window menu, and select 'Musical Typing.' The Musical Typing window will open, showing the Mac keys that correspond to musical keys. The Musical Typing window will also display key assignments for Pitchbend, Modulation, Sustain, Octave, and Velocity.
