Skip to Main Content
Idaho State University

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
B
B
B1
B2
B3
BBS
BCC
BCD
BCI
Bd
BER
Bit
BIU
BPI
BPS
BR
BSA
BSE
Bug
Bus
BW
Big Red Switch*
  • n. [IBM] The power switch on a computer, esp. the `Emergency Pull' switch on an IBM mainframe or the power switch on an IBM PC where it really is large and red. "This !@%$% bitty box is hung again; time to hit the Big Red Switch. " Sources at IBM report that, in tune with the company's passion for TLAs, this is often abbreviated as `BRS' (this has also become established on FidoNet and in the PC clone world). It is alleged that the emergency pull switch on an IBM 360/91 actually fired a non-conducting bolt into the main power feed; the BRSes on more recent mainframes physically drop a block into place so that they can't be pushed back in. People get fired for pulling them, especially inappropriately (see also molly-guard). Compare power cycle, three-finger salute, 120 reset; see also scram switch.