You are black, the bot is white. Place a disc so one or more of the bot's discs are trapped in a straight line between your new disc and another of yours — they flip to black. You must play a flipping move if one exists; otherwise you pass. When neither side can move, whoever has more discs wins.
Why having more discs is a trap
Only the count at the very end decides the game, and the count in the middle is close to meaningless. Every disc you own is a disc the opponent can flip, so a board where you hold thirty of forty pieces usually means you have taken lots of edges of your own colour that are still exposed. Strong players are often behind on discs until the last ten moves.
What matters instead is how many legal moves each side has. If you can reduce the opponent to one or two options, they are forced to play whatever you left them — and often that is a move that hands you a corner. This idea is called mobility, and it is the single biggest gap between a beginner and a club player.
Corners, edges and the squares next to them
A disc in a corner can never be flipped, because flipping requires trapping a line between two discs and a corner has no square beyond it. Corners are therefore permanent, and they anchor the two edges that meet there, which is why almost every game turns on who gets them.
The three squares surrounding each corner are the most dangerous on the board. The diagonal one in particular — the X-square — usually gives the corner away immediately, because it lets the opponent play into the corner with your own disc as the anchor. If you take nothing else from this page, take this: avoid the diagonal neighbour of an empty corner.
Edges are safer than the middle but not free. An edge disc with gaps on either side can still be trapped along that edge, so a solid, unbroken run reaching a corner is worth far more than scattered edge pieces.
An opening plan you can follow
Play towards the centre for the first ten or so moves and flip as few discs as you can. Small, quiet positions keep your options open.
Count the opponent's legal moves each turn. If the number is dropping, your position is improving no matter what the disc count says.
Never take a corner-adjacent square just because it flips a lot. That is exactly the bait the position is offering.
If every move you have is bad, choose the one that gives away the least permanent territory — an interior square over an edge, an edge over a corner neighbour.
In the last ten moves, switch to counting discs properly. The positional rules stop applying once no corner is left to lose.
They are almost identical. Othello is a standardised, trademarked version of the older game Reversi, with a fixed starting position of four discs in the centre.
How do you win at Othello?
You win by having the most discs of your colour when the board fills or neither side can move. Strong play values the corners (which can't be flipped) and mobility over grabbing discs early.
Can I play against a friend?
Yes. Choose 2-players mode for pass-and-play on the same device, or play against the computer at three difficulty levels.
Why is Othello called "a minute to learn, a lifetime to master"?
That is the game's famous slogan, and it fits. The rules — trap and flip — take a minute to explain, but good play is deeply counter-intuitive: having fewer discs mid-game is often better, and ideas like mobility, edge shape and parity keep rewarding study for years.
Is there a world championship for Othello?
Yes. The World Othello Championship has been held nearly every year since 1977, bringing together national champions from many countries, with Japanese players historically the most successful. Top games are decided by tiny margins and precise endgame counting, and studying them is a great way to improve.
Does Othello have named openings like chess?
Yes. Black's four possible first moves are symmetrical, so theory really starts with White's reply — perpendicular, diagonal or parallel. From there, well-known lines carry names like the Tiger and the Rose, and serious players memorise them just as chess players study openings.