The decimalisation of British currency in 1971, when the ancient system of pounds, shillings and pence was replaced with decimal currency. Years in the making, the operation involved minting billions of coins, converting millions of machines and teaching the entire nation how to cope with this colossal conversion. It sparked the largest public information campaign the country had ever seen, complete with TV dramas, scantily clad women dubbed 'Decimal Dollies' and a song by Max Bygraves