What does it mean to mount or unmount a disk image?

Mounting a hard disk makes it accessible by the computer. This is a software process that enables the operating system to read and write data to the disk. Most disks are automatically mounted by the operating system when they are connected.Unmounting a disk is, not surprisingly, the opposite of mounting a disk. It takes a mounted disk and makes it inaccessible by the computer. External storage devices should typically be unmounted before being disconnected to avoid corrupting files.