The pound sterling (symbol: £; ISO code: GBP), commonly called
the pound, is the official currency of the United Kingdom, the
Isle of Man, Channel Islands, the British Overseas Territories
of South Georgia and the South Sandwich Islands, British
Antarctic Territory and Tristan da Cunha. It is subdivided into
100 pence. Sterling is the fourth most traded currency in the
foreign exchange market, after the US dollar, the euro and the
Japanese yen. Together with those three currencies it forms the
basket of currencies which calculate the value of IMF Special
Drawing Rights, with a 11.3% weighting (the 3rd greatest) as of
2011. Sterling is also the third most held reserve currency in
global reserves. As a member of the European Union, the United
Kingdom could adopt the euro as its currency. However, the
subject remains politically controversial. Gordon Brown, then
Chancellor of the Exchequer, ruled out membership for the
foreseeable future, saying that the decision not to join had
been right for Britain and for Eu