An interesting application or implementation of trees is the playing of games such as tie-tac-toe, chess, nim, kalam, chess, go etc.

We can depict the sequence of possible moves by mean of a game tree in which the root signifies the initial situation and the branches from the root signifies the legal moves that the first player could make. At the next level down, the branches corresponds to the legal move by the second player in condition and so on, with branches from vertices at even levels signifying the moves by the 1st player and from the vertices at odd levels depicting the moves by the 2nd player.

Eg. Tic-tac-toe