Sliding puzzle

The pieces to be moved may consist of simple shapes, or they may be imprinted with colours, patterns, sections of a larger picture (like a jigsaw puzzle), numbers, or letters.

In manufactured wood and plastic products, the linking and encaging is often achieved in combination, through mortise-and-tenon key channels along the edges of the pieces.

In at least one vintage case of the popular Chinese cognate game Huarong Road, a wire screen prevents lifting of the pieces, which remain loose.

However, the mechanical fixtures are usually not essential to these puzzles; the parts could as well be tokens on a flat board that are moved according to certain rules.

sliding puzzle with square tiles of equal size can be represented by