Data Cell

An early magnetic card mass storage device from IBM. Used in the early 1960s and designed by Alan Shugart, who later engineered the hard disk and floppy disk, it was IBM's first direct access storage system.

Each Data Cell cartridge contained 200 3x15" cards ("tape strips") for a total of 40MB, and each Data Cell could hold 10 cartridges. With up to eight units connected to one computer, the Data Cell had huge direct access storage potential. The card was extracted from the cartridge, wrapped around a rotating drum for reading and writing and returned. More than 100 Data Cell units were installed worldwide during the 1960s. Although being able to access a single card in half a second was a mechanical marvel, the magnetic tape cards were very susceptible to wear, and returning the card to its cartridge was problematic. All three magnetic card systems of that era (IBM Data Cell, NCR CRAM and RCA RACE) had a short lifespan because magnetic disks were becoming the norm by the end of the 1960s. See RACE and CRAM.

A Data Cell Carousel

Each Data Cell unit could hold 10 cartridges on its carousel for a total of 400 megabytes or 800 million decimal digits. This image was taken from the Introduction to IBM Data Processing Systems textbook written in 1968. (Image courtesy of International Business Machines Corporation. Unauthorized use not permitted.)

A Data Cell Strip

The tape strip on the right is a Data Cell card. Storing 200KB, it resided with 199 other strips in the cartridge. (Image courtesy of Frank da Cruz, www.columbia.edu/acis/history)