Symbols on computers (was: Wang 300 Calc)

Brent Hilpert hilpert at
Mon Sep 10 01:16:42 CDT 2007

Mr Ian Primus wrote:
> > Keeping things on-vintage, when were icons first
> > used on PeeCee
> > hardware?
> - the power switch was typically marked with a 1 and a
> 0 (of course, they were real switches too, none of
> this soft-power stuff). And pushbuttons were typically
> labeled with 1/0. Anyone know when this symbol got
> established?

I'm of the impression the 0 and 1 for power switches is an IBMism, at least I
think I first saw it on IBM equipment perhaps in the 70s, before others
took up with it. Something makes me think I've seen it on IBM equipment
older than that as well.

0 and 1 never made much sense to me for the power switch, inasmuch as 0 and 1 can
refer to lots of things besides main power, and the 0 is typically more of
circle than a 0. 0 and 1? Circle and stick?

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