Magnetic storage

Magnetic storage is a way of storing data that uses magnets to store binary data. It uses patterns of positive and negative magnetisation to store data using read/write heads, which can view and change the magnetisation. A few examples include hard disk drives, floppy disks, and magnetic stripes.

Magnetic Storage Media

Longitudinal recording and perpendicular recording, two types of writing heads on a hard disk
The programmable calculators of the HP-41-series (from 1979) could store data via an external magnetic tape storage device on Mini-Cassettes.
Hard drives use magnetic memory to store giga- and terabytes of data in computers.

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