15Puzzle is a really simple game. The player is expected to order the numbers as follows:

You are bounded to a 16 square box, and can move only one square at a time.
Do it in the least possible steps. And yes, each one of the puzzles you get here can be solved.

1 | 2 | 3 | 4 |

5 | 6 | 7 | 8 |

9 | 10 | 11 | 12 |

13 | 14 | 15 |