A jigsaw puzzle is a tiling puzzle that requires the assembly of, often oddly shaped, interlocking and tessellating pieces. Each piece usually has a small part of a picture on it; when complete, a jigsaw puzzle produces a complete picture. In some cases more advanced types have appeared on the market, such as spherical jigsaws and puzzles showing optical illusions.
Jigsaw puzzles were originally created by painting a picture on a flat, rectangular piece of wood, and then cutting that picture into small pieces with a jigsaw, hence the name. John Spilsbury, a London cartographer and engraver, is credited with commercializing jigsaw puzzles around 1760. Jigsaw puzzles have since come to be made primarily of cardboard.