Alan Freedman -- The Computer Language Company - Computer Desktop Encyclopedia
Computer Desktop Encyclopedia
Longest-Running Tech Reference on the Planet

A CDE Definition

You'll love The Computer Desktop Encyclopedia (CDE) for Tech Term of the Day (TTOD)

LOOK UP ANOTHER TERM


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 IBM.)






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)






Personal Use Only

Before/After Your Search Term
BeforeAfter
data bitsdata center
data breachdata center container
data broadcastdata center cooling
data brokerdata center hosting
data busdata circuit-terminating equipment
data carddata cleansing
data carouseldata cloud
data carrierdata code
data cartridgedata collaboration
data cassettedata collection

Terms By Topic
Click any of the following categories for a list of fundamental terms.
Computer Words You Gotta KnowSystem design
Job categoriesUnix/Linux
Interesting stuffPersonal computers
InternetIndustrial Automation/Process Control
Communications & networkingAssociations/Standards organizations
HistoryDesktop publishing
Audio/VideoGraphics
MainframesSecurity
ProgrammingHealthcare IT
System design