Permanent peripheral storage, which is typically a hard disk drive, solid state drive (SSD) or USB drive. "Mass" is an old term that refers to large amounts of permanent storage in contrast with the smaller amount of "RAM" or "main memory," which is the computer's temporary workspace (see
memory). See
flash memory,
USB drive,
magnetic disk,
optical disc and
magnetic tape.
Mass Storage on a Deck of Cards
In the 1960s, a roomful of these Card Random Access Memory (CRAM) units provided 176 megabytes of direct access mass storage, a huge capacity for that era. See
CRAM for more details.
(Image courtesy of NCR Corporation.)