Tangram is an ancient Chinese game for one player. A Tangram set consists of seven pieces: two large triangles, one medium sized triangle, one square, one parallelogram, and two small triangles, cut from a large square as shown.

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Marketed sets are readily available, but it is easy to make a Tangram from any durable material. Note the relative areas of the pieces: the medium triangle, the square and the parallelogram each cover the same area, the large triangles cover twice this area, and the small triangles cover half this area.

The purpose of the Tangram is to make silhouettes of everyday objects. There are two ways to do this: either to make one's own, or to find ways to put the pieces together to match published sets of silhouettes. Despite there being only seven pieces, this is often quite challenging, mainly due to the confusing relative lengths of the piece edges.

The pieces of the Tangram can be put together to make many elementary shapes, including squares, rectangles, parallelograms, and triangles. Some examples of more complex silhouettes are shown below.

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House

The pieces that make up the Tangram turn out to be incredibly versatile, and thousands of recognisable and interesting shapes can be constructed. Many attempts have been made to find other sets of pieces, but none have been as successful as the Tangram.