Non-volatile memory, NVM or non-volatile storage is a type of computer memory that can retrieve stored information even after having been power cycled (turned off and back on).
Whereas Volatile memory is the memory that can not be retrieved after having been power cycled.
Examples of non-volatile memory include read-only memory, flash memory, ferroelectric, most types of magnetic computer storage devices (e.g. hard disk drives, floppy disks, and magnetic tape), optical discs, and early computer storage methods such as paper tape and punched cards.