Big Red Switch
[IBM] The power switch on a computer, especially 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 TLA
s, this is often abbreviated as "BRS" (this has also become established on FidoNet and in the IBM PC
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