Hehe, it's all pounds and pence. we have notes to the value of £5, £10, £20 and £50 and the coins go 1p (pence), 2p, 5p, 10p, 20p, 50p, £1 and £2
'Quid' is just a slang term for pound so twenty quid is twenty pound. Other slang terms are 'bob' - 5p, score - £20, tonne - £100...