Printer Friendly
Dictionary, Encyclopedia and Thesaurus - The Free Dictionary
3,895,516,960 visitors served.
forum Join the Word of the Day Mailing List For webmasters
?
Dictionary/
thesaurus
Medical
dictionary
Legal
dictionary
Financial
dictionary
Acronyms
 
Idioms
Encyclopedia
Wikipedia
encyclopedia
?

Data Cell

    0.01 sec.
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)


Want to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit the webmaster's page for free fun content.
?Page tools
Printer friendly
Cite / link
Feedback
Mentioned in?  References in periodicals archive?   Encyclopedia browser?   Full browser?
No references found
 
Build your own contingency table With data cells at A1:B200 of a Spreadsheet, we will form a contingency table at E2:F3 At D2 type "Female" and at D3 type "Male".
The data matrix coding, which government agencies call UID for unique edientification and are beginning to require for all their components, can be read even after 22% of the data cells are damaged.
 
 
 
Encyclopedia
?

Terms of Use | Privacy policy | Feedback | Advertise with Us | Copyright © 2012 Farlex, Inc.
Disclaimer
All content on this website, including dictionary, thesaurus, literature, geography, and other reference data is for informational purposes only. This information should not be considered complete, up to date, and is not intended to be used in place of a visit, consultation, or advice of a legal, medical, or any other professional.