Quote
"Note for young people and Americans; 1 shilling = 5p (pee or pence). The origional British monetary sysytem, 2 farthings = 1 ha'penny. 2 ha'pennies = 1 penny. 3 pennies = a thrupeny bit. 2 thrupences = a sixpence (or tanner). 2 sixpences = 1 shilling (or bob). 2 bob = a florin. 1 florin and one sixpence = half a crown. 4 half crowns = 10 bob note. 2 ten bob notes = 1 pound (or 240 pennies). 1 pound and 1 shilling = a guinea.
The british resisted decimalised currency for a long time because they thought it was too complicated."
T. Pratchett

I just love that and it explained it much better than any damm school I went to!