Connect 5

Connect-Five is a tic-tac-toe-like two-player game in which players alternately place pieces on a vertical board 8 columns across and 7 rows high. Each player uses pieces of a particular color (commonly black and red, or sometimes yellow and red), and the object is to be the first to obtain five pieces in a horizontal, vertical, or diagonal line. Because the board is vertical, pieces inserted in a given column always drop to the lowest unoccupied row of that column. As soon as a column contains 7 pieces, it is full and no other piece can be placed in the column.