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The tangram is a dissection puzzle consisting of seven flat shapes. The objective of the puzzle is to form a specific shape (given only an outline or silhouette) using all seven pieces, which may not overlap. It is reputed to have been invented in China during the Song Dynasty. A Chinese psychologist has termed the tangram "the earliest psychological test in the world", albeit one made for entertainment rather than analysis.
Source : http://en.wikipedia.org/wiki/Tangram