Share disk is a macOS Recovery feature that allows you to share the internal storage of your Mac with Apple silicon as an external drive with another Mac. This feature is useful for transferring files between two Macs, or for troubleshooting issues with your Mac with Apple silicon. Share disk is only available on Mac computers with Apple silicon, and it requires a Thunderbolt or USB cable to connect the two Macs. To use Share disk, you need to start up your Mac with Apple silicon in macOS Recovery, then choose Utilities > Share Disk. On the other Mac, you can access the shared disk from the Finder or Disk Utility. References: = Use macOS Recovery on a Mac with Apple silicon, How to access macOS Recovery on Apple Silicon M1 Mac, Apple Silicon Macs to Feature New Boot and Recovery Interface, New Mac …, How to Enter Recovery Mode on a Mac with Apple Silicon