Kumiki is a Japanese word which means "to join wood together". In Japan, the term "kumiki" refers to several different varieties of woodcraft, especially figural wooden interlocking puzzles or, in a broader sense, any wooden construction toy. They are also known as "burr puzzles." Each puzzle is handcrafted, and each is displayed as a small work of art, created in precision as is evident in how exact the puzzle pieces together.
These puzzles may have been used by master woodworkers as they tutored their apprentices in the art of constructing wooden buildings using interlocking pieces in the absence of metal parts or fasteners.
Tsunetaro Yamanaka (1874-1954) was the first craftsman to design and construct puzzles that resembled building and vehicles as well as abstract shapes like spheres and cubes. His descendants continued this kumiki tradition, still creating new puzzles including animal shapes. Today, Tadaaki Yamanaka, great grandson of Tsunetaro, continues his work.