Lazy medieval
The term Graham Nelson applies (in "The Craft of Adventure" ) to the cultural mythology described in the classic computer adventure games, "where anything prior to the invention of gunpowder goes, all at once, everything from Greek gods to the longbow (a span of about two thousand years). In fact, anything an average reader might think of as `old world' will do, the Western idea of antiquity being a huge collage."
The lazy medieval setting grants the game designer license to throw in anything that comes to mind, relying on text adventure convention and "common" knowledge of Dungeons & Dragons to fill in the blanks. The result is rapid development and low memory use, but these benefits come at the expense of plot and mimesis.
Original --JdBerry - 10 Sep 2002