Tic Tac Toe: играть онлайн бесплатно

The board sits on a page of squared school notebook paper, and the marks draw themselves in blue and red ink, stroke by stroke.

How to play tic tac toe

Players take turns placing a mark in an empty square, one using X and the other O. The first to line up three marks wins, on any of the eight lines: three across, three down or two diagonal. If all nine squares fill up with no line, the game is a draw.

Against the computer: a run of up to 20 games

Pick one of three levels. Easy places its mark at random more than half the time, Medium slips about once in five moves, and Unbeatable works every game through to the end and never errs. You play a run: games follow on automatically, you take turns going first, and one loss ends the whole run. On Easy a win pays 5 points and a draw 2. On Medium it is 12 and 5. Unbeatable cannot be beaten, but every draw is worth 10, so 20 games without a loss come to 200 points. Your best for each level is kept separately, and your run score goes on the leaderboard.

Tic tac toe 2 player

On one phone you hand it across after each move, while the bar at the top shows whose mark is next and the score for the session. X and O take turns opening, so nobody keeps an edge. Tic tac toe online with friends works by invitation: send a link, each of you plays on your own screen, and whoever opened the room places the first X.

Tic tac toe strategy going first

With perfect play from both sides the game is always a draw, so wins come from the other player's mistakes. Your strongest idea is the fork, a position with two threats at once, since your opponent can only block one. Open in a corner. If the reply lands anywhere except the centre you have a forced win, because after a corner only the centre saves the second player. If they do take the centre, play the opposite corner. They must now answer on an edge, and a corner reply loses.

Tic tac toe strategy going second

The computer opens every other game in a run. We checked all 255,168 possible games, and the answers are short. After a corner, take the centre. After the centre, take a corner, since every edge loses. After an edge, you are safe with the centre, either neighbouring corner or the opposite edge. Before each move, first check whether you have two in a line with the third square empty, and only then whether your opponent does.

A little history

Around the first century BC, Romans played terni lapilli, meaning three pebbles at a time. The name noughts and crosses first appeared in print in 1858, in the journal Notes and Queries. In 1952 A. S. Douglas programmed the game on the EDSAC computer at the University of Cambridge, creating one of the first known video games.

Controls and looks

Tap or click an empty square. On the keyboard the arrows move around, Space or Enter places your mark, and keys 1 to 9 take a square straight away, counting from the top left.