A game of Ataxx begins with four
pieces on the board: a dark colored piece in the upper left
and lower right corners, and a light colored piece in the
lower left and upper right corners.  Dark moves first; by
default, this player is human.
To make a move, click on one of your discs.  Available moves
for that disc will be outlined in white.  For a disc in the
middle of an unobstructed board, there are 24 possible moves,
illustrated in .  Click on one of
the eight squares adjacent to the disc and you will add a new
disc to the board.  Click on one further away, and the disc
will move there, jumping any obstacles in its path.  You
cannot move a disc into an occupied square, nor can you remove
a disc from the board.
When you move or add a disc to a position adjacent to one or
more of your opponent's discs, you capture those discs.  When
you capture them they change color to indicate your
possession, and you can move them or add discs next to them as
you would any other disc in your possession.  This is good for
you and bad for your opponent.
This means that, strategically, an L-shaped formation of discs
is bad to have, because it allows an opponent to capture more
discs with a single move.  The worst sort of formation would
be donut-shaped, because it would allow the
capture of eight pieces at once.
