A puzzle is a problem or enigma presented as entertainment; that is written down, acted out, etc.
Many puzzles stem from serious mathematical or logistical problems (see packing problems and tour puzzles).
Others, like chess problems, are derived from board games.
Others again have been devised for the sole purpose of being brain teasers.
The history of puzzles goes back many thousand years, Tangram being one of the earliest and still one of the most popular puzzles. In certain temples of Japan monks used to write mathematical puzzles on temple walls.
