History and Variations
The game was originally marketed in 1974 as Connect Four by Milton Bradley. It used a plastic rack with six rows and seven columns, and each player dropped coloured counters down the columns to make their moves.
There are many variations on the board size, the most commonly used being 7x6, 8×7, 9×7, and 10×7.
Hasbro also marketed a version based on a 5 x 5 board called Connect 4 Shots with a real-time element.