tangrams

Tangrams are a puzzle consisting of seven flat pieces, known as tans, that can be rearranged to form a wide variety of shapes. The standard set includes two large right triangles, one medium right triangle, two small right triangles, a square, and a parallelogram. All seven pieces are cut from a single square; the challenge is to use every piece exactly once to assemble a given silhouette without overlaps or gaps.

The puzzle is widely associated with China, where the Chinese name qi qiao ban (七巧板) translates as "seven clever pieces." Tangram literature and artifacts began circulating in the 19th century, and the puzzle was subsequently popularized in Europe and North America in the early 1800s. The name tangram is the Western form of the term.

Tangrams are used as an educational tool and a recreational pastime. They encourage geometric reasoning, spatial visualization, and problem solving. Puzzles range from simple arrangements suitable for young children to challenging silhouettes for adults, including animals, people, letters, and abstract shapes. The set’s requirement to place all pieces without overlap constrains possible solutions and fosters exploration of symmetry, congruence, and area. Variants exist, including different sizes and digital versions for computers and mobile devices, but the seven-piece tangram remains the best-known configuration.