Abstract combinatorial game, usually played on paper, learned by many during childhood. Start with a grid of dots, and two players take turns drawing lines between two dots adjacent horizontally or vertically. Completing a 1x1 box gains a point and another turn. It turns out to be quite an interesting and difficult game mathematically and computationally. Dots and Boxes Paper and Pencil Games.
Dots and Boxes is a pencil-and-paper game for two players (sometimes more). It was first published in the 19th century by Édouard Lucas, who called it la pipopipette. (wikipedia)