Spacial thinking

      Tangrams are possibly among the easiest of puzzles to make, and the among hardest to master.  The traditional tangram is composed of seven pieces - 2 large triangles, a medium sized triangle, 2 small triangles, a square, and a parallelogram - that will fit together into a perfect square, among thousands of other shapes.  The pieces themselves are called tans, while the images created with them are called tangrams.  The challenge of the puzzle is to create various shapes by arranging the pieces so that they touch, but do not overlap.  Patterns can vary from very easy to form [...]