Logic Pro X is a digital audio work station with creative tools for professional songwriting, beat making, editing, and mixing. When users are ready to take the next step up from Garageband, Logic Pro X is the best choice!
FL Studio is a complete software music production environment, containing everything you need in one package to compose, arrange, record, edit, mix and master professional quality music.
GarageBand is a Digital Audio Workstation that contains a complete sound library, including instruments, vocal effects, and much more.
Audacity is an open source multi-track editor that works on multiple platforms including Mac, Windows, and Linux.