It is an electronic form of an old mechanical sliding number/alphabet puzzle. It is equally popular among children as well as adults. It is a time based puzzle and the challenge is to complete the puzzle in the minimum possible time. The new exciting thing is - you can view the best timings of all the players who have played the game on a particular device.
You will feel compelled to play it again and again to beat your previous best scores. Playing this puzzle will improve your analytical and logical skills.