So VM volume usually takes up most of the storage space. VM (Virtual Machine): the volume that supplements your RAM to store files like sleepimage, swapfile, which is too large for RAM to run. Recovery: the volume that contains recovery system of your Mac, which you can boot into by holding CMD + R during startup. Preboot: the volume that manages boot, which is created during macOS High Sierra update to support booting to Macintosh HD. Macintosh HD: the volume with macOS software system installed, which usually shown in Disk Utility as Macintosh HD. For example, a standard macOS startup APFS container includes volumes as follow:
A physical disk could have multiple containers and a container includes multiple virtual volumes, which all share the storage space of the container. In APFS, the new file system that Apple introduced to macOS High Sierra and later, a container is similar to a partition in other file systems. What is Other Volumes in Container on Mac?
