An optical disc (CD, DVD) or USB drive that contains a bootable program that takes control of the computer. Computers are typically configured to look for the OS on a CD or DVD first and then the ...

Apple Software Restore lets you clone your Mac even with a Signed System Volume. Here's how to use it to copy your Mac's storage.

Having bootable media ready can be a real lifesaver ... Any file that ends in .iso is an exact copy of a disk. It's a virtual copy of a CD or DVD, with the same file structure and the same data.

They can also hold an operating system and be used to boot the computer (see bootable disk). See sneakernet. USB drives are generally formatted as FAT or exFAT, which makes them compatible between ...