The goal is to arrange the numbered tiles in sequential order (usually 1, 2, 3,... from left to right, top to bottom), leaving the empty space in the last position.
Click on a tile that is adjacent (horizontally or vertically) to the empty space.
The clicked tile will slide into the empty space.
Continue sliding tiles until they are all in the correct order.
The "New Game / Shuffle" button will scramble the tiles for a new challenge.
You can change the grid size for different levels of difficulty.