All your instruments can be loaded from here by choosing a category, then an instrument preset.
Build up layers of loops, instruments, and audio recordings, then use the sliders here to adjust the level of each one.
Copy, paste, and arrange clips on the timeline. Drag the ends of loops to make them longer. Snap clips to ensure correct timing.
You can sort loops using tags and names, download just those you want, and drag them into a project to create backing tracks.
MIDI and audio can be edited. This means sounds you’ve recorded as well as content from GarageBand’s library.