GarageBand 10.1.6
Apple has released GarageBand 10.1.6, providing the standard unspecified “improvements and bug fixes” in its one-line release note. However, an Apple security update support page indicates that the new version patches a vulnerability related to a memory corruption issue that could lead to arbitrary code execution after opening a maliciously crafted GarageBand project file. Apple fixed the issue through improved memory handling. (Free with new Macs or $4.99 new from the Mac App Store, free update, 956 MB, 10.9+)
Not for those of us using Macs too old to run Sierra. I have Garage Band 6.0.5.
You aren't missing anything with the newer GB except a confused UI that seems to favor people who use loops and hiphop beats instead of recording instruments and vocals. It should be called DJ.