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?
