pdp-20 n. the most famous computer that never was. pdp-10 computers
   running the tops-10 operating system were labeled `decsystem-10' as
   a way of differentiating them from the pdp-11. later on, those systems
   running tops-20 were labeled `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 color 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.


see also:
pdp-10 tops-10 tops-20 

pdp-20
     
        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
     
     
see also:
pdp-10 tops-10 pdp-11 tops-20 operating system jargon file