A jigsaw puzzle is a tiling puzzle that requires the assembly of often oddly shaped interlocking and mosaiced pieces. Typically, each individual piece has a portion of a picture; when assembled, they produce a complete picture. Beginning in the 18th century, jigsaw puzzles were created by painting a picture on a flat, rectangular piece of wood, then cutting it into small pieces. Despite the name, a jigsaw was never used. John Spilsbury, a London cartographer and engraver, is credited with commercializing jigsaw puzzles around 1760. They have since come to be made primarily of cardboard. Typical images on jigsaw puzzles include scenes from nature, buildings, and repetitive designs—castles and mountains are common, as well as other traditional subjects. However, any kind of picture can be used. Artisanal puzzle-makers and companies using technologies for one-off and small print-run puzzles utilize a wide range of subject matter, including optical illusions, unusual art, and personal photographs. In addition to traditional flat, two-dimensional puzzles, three-dimensional puzzles have entered large-scale production, including spherical puzzles and architectural recreations. In recent years, a range of jigsaw puzzle accessories including boards, cases, frames, and roll-up mats has become available to assist jigsaw puzzle enthusiasts. While most assembled puzzles are disassembled for reuse, they can also be attached to a backing with adhesive and displayed as art.