From Paper Tape to Data Sticks: The Evolution of R...
The Compact Cassette
Philips developed the Compact Cassette--two small reels of magnetic tape in a plastic shell--as a format for audio recordings in the 1960s. HP briefly used that format in its HP 9830 (1972), but the compact cassette didn't gain widespread popularity for digital data until a few years later, when personal computer hackers, hungry for cheap storage, commandeered the format. The medium remained popular in bargain computers of the late 1970s and early 1980s because both to the media and the drive were so inexpensive (many computers could load and save data from a standard audiocassette player).
Photos: Benj Edwards/Commodore
From Paper Tape to Data Sticks: The Evolution of Removable Storage