Audacity

Audacity is a free, open source audio editor. It is simple, yet has a lot of depth. It is great for times where GarageBand is overkill for a simple recording task. And it concentrates on just audio recording and editing, which can make it more powerful than GarageBand for that. You can edit with precision, apply filters and effetcs, and export in a variety of formats. Even if recording or editing audio is a rare task for you, or you already own another sound editing application, you should download the free Audacity application and add it to your arsenal of programs.