Skip to Main Content
Idaho State University home

Glossary

Filter:
# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
P
P&D
P3P
PA
PAA
PAD
PAE
PAL
PAP
PAX
PBD
PBX
PC
PCA
PCS
PCZ
PD
Pdl
PDN
PDR
PDS
PDU
PES
PIP
PIX
PKA
PKC
PL
PLA
PM
PMD
PMO
PMP
Pod
POM
Pop
PPL
PPN
PPS
Ps
PSL
PSN
PTR
PTT
PUC
PUT
PVC
PWA
PX
Punched Card
  • n. obs. [techspeak] (alt. `punch card') The signature medium of computing's Stone Age, now obsolescent outside of some IBM shops. The punched card actually predated computers considerably, originating in 1801 as a control device for mechanical looms. The version patented by Hollerith and used with mechanical tabulating machines in the 1890 U. S. Census was a piece of cardboard about 90 mm by 215 mm. There is a widespread myth that it was designed to fit in the currency trays used for that era's larger dollar bills, but recent investigations have falsified this. IBM (which originated as a tabulating-machine manufacturer) married the punched card to computers, encoding binary information as patterns of small rectangular holes; one character per column, 80 columns per card. Other coding schemes, sizes of card, and hole shapes were tried at various times. The 80-column width of most character terminals is a legacy of the IBM punched card; so is the size of the quick-reference cards distributed with many varieties of computers even today. See chad, chad box, eighty-column mind, green card, dusty deck, lace card, card walloper.