Pentomino
A pentomino is a polyomino of five squares.
The ancient pentomino puzzle uses free pentominoes.
The shapes
There are 12 free pentominoes. Six of them are chiral, making a total of 18 one-sided pentominoes.
Symmetric
I |
T |
U | |||
V |
W |
X |
Chiral
These come in mirrored pairs:
R and F |
S and Z |
J and L | |||
Y' and Y |
H and N |
P and Q |