Chess960[0] aka Fischer Random aka "Freestyle Chess" (the last is a name chess.com has been using") is a fairly popular variant with 960 possible starting positions.<p>The way I'm interpreting this, 324 is different in that the rooks & kings are fixed, but the position is asymmetric.<p>Is it called 324 because there are 324 possible starting positions? Also, I'm inferring that this is popular in computer chess specifically, is there a reason for that?<p>[0]: <a href="https://en.wikipedia.org/wiki/Chess960" rel="nofollow">https://en.wikipedia.org/wiki/Chess960</a><p>edit: there's a quote from the inventor in the wiki that answers my first question and sort of answers the second:<p>> This version has huge advantages over chess960. First, no special castling rules, any engine or GUI or human can play with no instruction after seeing the initial position. Second, since all but 18 of the 324 positions are asymmetrical, opening play should be much more interesting and complex. Third, the normal positioning of the rooks and kings and normal castling makes the game feel closer to normal chess. Fourth, matches of up to 648 games can be played with no repeat positions, generally enough for most purposes. Most important, no matter how many cores or how much time the engines get, there should be plenty of decisive games for the foreseeable future since many positions are at least not too far from the win/draw line.