Connect 4

The “vertical strategy game” Connect 4 originated in the USA where it was designed by renowned independent toy designer Ned Strongin, with Dr Howard Wexler – a City College graduate with a PhD in psychology – and manufactured by Milton Bradley.

The object – to be the first to get four discs in a row, whether horizontally, vertically or diagonally – should have been easy, but it wasn’t.

Playing on a vertical grid made up of seven columns and six rows, the advantage always fell to the first player.

Yet during the to-ing and fro-ing of this turn-based game (each player had 21 discs to start), players would seek to frustrate and outwit their opponent by thinking ahead strategically.

It was this degree of complexity that saw the game fly off shop shelves following its 1974 debut. It was introduced in the UK two years later.

The key to winning was to pop the first disc into the centre column since, in a game played perfectly from that point on, the opponent would always lose within 41 moves. But with 42 pieces to place, and taking into account that a Connect 4 board has a staggering 4,531,985,219,092 possible positions, anything could happen.

As well as coming in a multitude of sizes – including Giant Connect 4 that can be played outdoors – the game and its underlying concept have been turned into a series of videogames in recent years.

There have been fresh variations too, including a 3D version for up to four players called Connect 4×4 and another called Connect 4 Twist & Turn, which is based around a tower made up of five twisting layers.