Simon

Watch the colour sequence, then repeat it back. It grows every round — how far can your memory stretch?

Simon arrived in 1978, designed by Ralph Baer — who had already built the first home console — and Howard Morrison, after they saw Atari's Touch Me. Its launch party at Studio 54 is one of the more improbable marketing decisions in toy history.

The sequence grows by one each round, which sounds gentle and is not, because recall of an ordered list degrades sharply past about seven items. The technique that beats raw memorisation is chunking: grouping the sequence into threes or fours and remembering the groups, which is the same trick that makes phone numbers memorable.