The most famous computer that never was.
PDP-10 computers
running the
TOPS-10 operating system were labelled
"DECsystem-10" as a way of differentiating them from the
PDP-11. Later on, those systems running
TOPS-20 were
labelled "DECSYSTEM-
20" (the block capitals being the result
of a lawsuit brought against DEC by Singer, which once made a
computer called "system-10"), but contrary to popular lore
there was never a "PDP-
20"; the only difference between a 10
and a
20 was the
operating system and the colour of the
paint. Most (but not all) machines sold to run
TOPS-10 were
painted "Basil Blue", whereas most TOPS-
20 machines were
painted "Chinese Red" (often mistakenly called orange).
[
Jargon File]
(1994-12-21)