Nim is a simple 2-player game. There are 3 piles of stones. On each turn, a player must remove one or more stones from any single pile, then click Done. Whoever takes the last stone wins.
The starting number of stones in each pile is semi-randomly set by the computer at the start of each game.
Nim may be played against the computer or against another human. When playing against the computer, the human player always goes first.