Magnetic storage is the manipulation of magnetic fields on a medium in order to record audio, video or other data.
Magnetic storage has been around in many forms since 1888 by Oberlan Smith, who publicized his audio recording on a wire in Electrical World. In broad terms, magnetic storage mostly works very similarly to Smith's recording. Read and write heads (either combined or separate) are used to align the magnetic fields on the recording medium. A great variety of analog and digital devices using magnetic storage.
Many types of magnetic storage involve a tape medium ether on a real or in a cassette that is moved by read and write heads. Similar working devices include real to real tapes, 8 track tapes and audio cassettes as well as video storage mediums of VHS, D-VHS and Betamax.
In main computer storage mechanisms have generally involved a spinning disc or platter and read write heads on an armature (though there have also been tape drives and magnetic drums used in the past). Disk storage solutions include floppy drives (8, 2.5 and 5.25 inch alike), magneto-optical rewritable discs as well as hard drives including helium hard drives. These technologies have taken us from capacities of kilobytes to numerous terabytes and bytes per second to 100+ MB per second. Laser switched magnetic storage hard drives have promised to improve performance by 1000 times in the future.
MRAM (magneto resistive random access memory) is potentially the future computer RAM and main storage format. Storing data bits using magnetic charges instead of the electrical charges used by DRAM, MRAM has been demonstrated at superior speeds. Another benefit is MRAM's nonvolatile nature.