IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi. Both the hard disk drive and floppy disk drive were invented by IBM and as such
IBM 305 at U.S. Army Red River Arsenal, with two IBM 350 disk drives in the foreground
RAMAC mechanism at Computer History Museum
IBM 1311 disk drive with IBM 1316 removable disk pack at the Computer History Museum
IBM 2311 Disk Storage Drive, with its six platters
History of hard disk drives
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In 1953, IBM recognized the immediate application for what it termed a "Random Access File" having high capacity and rapid random access at a relatively low cost. After considering technologies such a
History of IBM magnetic disk drives
…History of the floppy disk History of hard disk drives List of IBM products…
Removable disk packs
Burroughs B-475 Disk Drive (circled)
Seagate 20 MB HDD and Western Digital Controller for PC