One of the common aspects of modern computer hardware is a technology known as a magnetic storage device. This is a technology available in multiple forms, such as a floppy disk drive, a tape drive and a hard drive.
A magnetic storage device works on a principal of magnetic charge. The basic premise is that a magnetizable medium, such as a metal wire, can be magnetized by an electric magnet. It can then be "read" magnetically and its recorded "data" played back.
Magnetic storage was first used for audio recording, and is generally referred to as magnetic recording. The basic principle is the same. Modern audio recording often uses a digital magnetic storage device.
A digital magnetic storage device records (stores data) in a stepped pattern. This is because a digital signal consisting of only two main states. A digital stream of data is as a binary signal containing a sequence of 1's and 0's, so only two magnetic states are necessary.
A magnetic storage device is a device that uses a magnetic head to read and write data to and from a magnetizable medium. The medium can be as basic as a plastic tape that is coated with fine particles of a metal, such as is found in audio recording and tape storage devices.
There are many types of magnetic storage devices. Audio tape is an early example of magnetic recording that later transitioned into use for computer data storage. A computer's hard disk is a more modern example of magnetic data storage. A floppy disk is yet another example.