Sterling is the currency of the United Kingdom and nine of its associated territories. The pound is the main unit of sterling, and the word pound is also used to refer to the British currency generally, often qualified in international contexts as the British pound or the pound sterling.
The Hatter's hat shows an example of the old pre-decimal notation: the hat costs 10/6 (ten shillings and sixpence, a half guinea).
A pound = 20 shillings = 240 silver pennies (formerly)
King Offa penny (eighth century)
Penny of Henry III, 13th century
The euro is the official currency of 20 of the 27 member states of the European Union. This group of states is officially known as the euro area or, more commonly, the eurozone. The euro is divided into 100 euro cents.
The European Central Bank seat in Frankfurt am Main
Euro coins and banknotes of various denominations