Crosswords are a kind of ludic puzzle involving language as token in their setting and language as target in their solving (as with other types of language play—see Chap. 1 ). They, like Scrabble in Chap. 17 , are based on the grid principle that originated in Words Squares as outlined in Chap. 9 whereby horizontal and vertical words intersect. Crosswords are big business nowadays; every day millions of people take on the setters.