- Normal moves: Put the mouse cursor over the piece you want to
move, push the mouse button,
move the cursor to the destination, and let the mouse button up.
- Castling: Move the king two squares left or right.
- En passant captures: Move the capturing pawn diagonally as if
doing a normal capture.
- Switching sides: Type 'g' (for "go") with the mouse over the board
to tell the computer to make the next move.
- Takebacks: Type 'b' to take back a move.
- Restart: Type 'r' to restart. Also used to claim a draw.
For the moment, pawns always promote to queens.