Squares (a.k.a. Dots and Squares) is a pencil and paper game for two players.

The game starts with a grid of dots. Players take turns in drawing either a horizontal or vertical line that connects two unconnected adjacent dots. This line represents one side of a square. Whenever a player closes a square (i.e., draws the fourth side of a square), he/she scores a point and takes another turn. The objective of the game is to close more squares than the opponent. The first player to close more than half of the potential squares in the board wins.

https://slideme.org/application/squares