alt=An incomplete board of Ultimate Tic-Tac-Toe.|thumb|Incomplete super tic-tac-toe game (the large 'X's and 'O's represent small boards that are won by that player).

Tic-tac-toe is an instance of an m,n,k-game, where two players alternate taking turns on an m×n board until one of them gets k in a row.

a "quantum generalization" of tic-tac-toe in which the players' moves are "superpositions" of plays in the classical game.