making a puzzle you need at least two pieces. One could think that a puzzle with
so little pieces must be simple, boring and probably not worth mentioning at all,
although a toddler can have a lot of fun connection two pieces of a simple
jigsaw. However not only toddlers can have some problems with puzzles of two
pieces. The next examples shows two puzzles which can even drive adults to
puzzle is made of two identical pieces. The problem looks very simple: make one
pyramid, but a lot of people need rather some time to find the solution, and some
even won't ever find it.