Tic-tac-toe, also spelled tick tack toe, or noughts and crosses as it is known in the UK, Australia, New Zealand, is a pencil-and-paper game for two players, O and X, who take turns marking the spaces in a 3×3 grid, usually X going first. The player who succeeds in placing three respective marks in a horizontal, vertical, or diagonal row wins the game.
The first known video game, OXO (or Noughts and Crosses, 1947) for the EDSAC computer played perfect games of tic-tac-toe against a human opponent.
Connect Four (also known as Four Up, Plot Four, Find Four, Four in a Row, and Four in a Line) is a two-player game in which the players first choose a color and then take turns dropping their colored discs from the top into a seven-column, six-row vertically-suspended grid. The pieces fall straight down, occupying the next available space within the column. The object of the game is to connect four of one’s own discs of the same color next to each other vertically, horizontally, or diagonally before one’s opponent can do so. There are many variations on the board size, the most commonly used being 7×6, followed by 8×7, 9×7, and 10×7.
The game was first sold under the famous Connect Four trademark by Milton Bradley in February 1974.
You’ll find a guide here.