evidence: The euro has become the second most traded currency behind the U.S. dollar. The official currency of the majority of the nations within the eurozone, the euro was introduced to the world markets on Jan. 1, 1999, with banknotes and coinage entering circulation three years later. [...] The Great British pound, also known as the pound sterling, is the fourth most traded currency in the forex market. Although the U.K. was an official member of the European Union, the country never adopted the euro as its official currency for a variety of reasons, namely historic pride in the pound and maintaining control of domestic interest rates. As a result, the pound is sometimes viewed as pure-play in the United Kingdom.