A puzzle of the class of spatial puzzles.
The soma cube is a cube, 3x3x3 units. It is subdivided into several unique pieces, each constructed of multiple 1x1x1 units attached.
The puzzle is to get all those pieces to fit together back into the body of 3x3x3.
Many people go on to use the cube pieces as a sculpture, trying to form minimalist shapes, instead of forming the basic cube. Hundreds or thousands of patterns are named after the animals and things they vaguely resemble.
The tangrams and pentominoes puzzles are somewhat related.