The most famous computer that never was. ef="module.php?name=Lexikon&file=search&eid=1&query=PDP-10">PDP-10 computers running the ef="module.php?name=Lexikon&file=search&eid=1&query=TOPS-10">TOPS-10 operating system were labelled "DeCsystem-10" as a way of differentiating them from the ef="module.php?name=Lexikon&file=search&eid=1&query=PDP-11">PDP-11. Later on, those systems running ef="module.php?name=Lexikon&file=search&eid=1&query=TOPS-20">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 ef="module.php?name=Lexikon&file=search&eid=1&query=operating system">operating system and the colour of the paint. Most (but not all) machines sold to run ef="module.php?name=Lexikon&file=search&eid=1&query=TOPS-10">TOPS-10 were painted "Basil Blue", whereas most TOPS-20 machines were painted "Chinese Red" (often mistakenly called orange). [ef="module.php?name=Lexikon&file=search&eid=1&query=Jargon File">Jargon File] (1994-12-21)

e="border-width:thin; border-color:#333333; border-style:dashed; padding:5px;" align="left">In addition suitable contents:
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ef="module.php?name=Lexikon&op=content&tid=1402">block ] [ ef="module.php?name=Lexikon&op=content&tid=1419">Blue ] [ ef="module.php?name=Lexikon&op=content&tid=1535">br ] [ ef="module.php?name=Lexikon&op=content&tid=1695">by ] [ ef="module.php?name=Lexikon&op=content&tid=1708">C ] [ ef="module.php?name=Lexikon&op=content&tid=1724">ca ] [ ef="module.php?name=Lexikon&op=content&tid=2000">Ch ] [ ef="module.php?name=Lexikon&op=content&tid=2001">ch ] [ ef="module.php?name=Lexikon&op=content&tid=2136">ck ] [ ef="module.php?name=Lexikon&op=content&tid=2247">co ] [ ef="module.php?name=Lexikon&op=content&tid=2322">colour ] [ ef="module.php?name=Lexikon&op=content&tid=2330">com ] [ ef="module.php?name=Lexikon&op=content&tid=2491">computer ] [ ef="module.php?name=Lexikon&op=content&tid=2545">con ] [ ef="module.php?name=Lexikon&op=content&tid=2976">D ] [ ef="module.php?name=Lexikon&op=content&tid=3151">de ] [ ef="module.php?name=Lexikon&op=content&tid=3176">DeC ] [ 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ef="module.php?name=Lexikon&op=content&tid=12133">su ] [ ef="module.php?name=Lexikon&op=content&tid=12162">suit ] [ ef="module.php?name=Lexikon&op=content&tid=12246">sy ] [ ef="module.php?name=Lexikon&op=content&tid=12312">system ] [ ef="module.php?name=Lexikon&op=content&tid=12359">T ] [ ef="module.php?name=Lexikon&op=content&tid=12588">th ] [ ef="module.php?name=Lexikon&op=content&tid=12721">to ] [ ef="module.php?name=Lexikon&op=content&tid=12744">TOP ] [ ef="module.php?name=Lexikon&op=content&tid=12753">TOPS-10 ] [ ef="module.php?name=Lexikon&op=content&tid=12754">TOPS-20 ] [ ef="module.php?name=Lexikon&op=content&tid=12787">tr ] [ ef="module.php?name=Lexikon&op=content&tid=12939">tw ] [ ef="module.php?name=Lexikon&op=content&tid=13008">ug ] [ ef="module.php?name=Lexikon&op=content&tid=13175">us ] [ ef="module.php?name=Lexikon&op=content&tid=13310">ve ] [ ef="module.php?name=Lexikon&op=content&tid=13877">ws ] [ ef="module.php?name=Lexikon&op=content&tid=14024">Y ]