So you're reading a novel set in Victorian London and someone gives someone "three and six". Welcome to the world of pounds, shillings and pence, money of Britain and parts of the Commonwealth before it went decimal in 1971. The rules: Then you get onto the other coins: The five pound note used to be pretty large by banknote standards. For those that are interested the coins and notes used in the modern, decimal system of currency (pounds and pence) are; There are some money slang terms: Notes were 10 s., £1, £5, £10, £20, £50, £100. In 1990 a pound coin was introduced, and the notes became: