Connect Four (also known as Captain's Mistress, Four Up, Plot Four, Find Four, Fourplay, Four in a Row and Four in a Line) is a two-player connection game in which the players first choose a color and then take turns dropping 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 objective of the game is to connect four of one's own discs of the same color next to each other vertically, horizontally, or diagonally. Connect Four is a strongly solved game. The first player can always win by playing the right moves.
https://en.wikipedia.org/wiki/Connect_Four
To play go here: http://connectfour3.divshot.io/