This Stock Puzzle consists of a 4x5 board with sliding blocks. One block is 2x2; the other blocks are 2x1, 1x2 and 1x1. The goal of the puzzle is to get the 2x2 block into the bottom position. There are variations of this puzzle based on differences in the initial position, or in the number of blocks of various sizes. It is sometimes known as the Dad's Puzzle, where the theme is a father trying to move around pieces of furniture, or the Pennant Puzzle. Examples of Klotski include: