Pentominoes are shapes made by connecting five equal-sized squares, each joined together along an edge. There are 12 of these shapes, named for the alphabet letter each resembles: T, U, V, W, X, Y, Z, F, I, L, P, N.

Since there 12 distinct pentomino shapes, each containing five squares, their total area is 60 squares. The challenge is covering a grid of 60 square units using the 12 pentominoes. With two players, each places a pentomino in turn. If one cannot move, he loses.

To move a pentomino-drag it with the mouse. To rotate it forward or backward, press keys: f, F, b, B. To reflect around the vertical or horizontal, press keys: v, h.

More information about Pentominoes along with numerous other resources can be found on Eric Harshbarger's Pentominoes Page.