Currency pair a dot or a dash. A widely traded currency pair is the relation of the euro against the US dollar, designated as EUR/USD. The quotation "EUR/USD 1.2500" means that one euro is exchanged for 1.2500 US dollars. Here, EUR is the base currency and USD is the quote currency(counter currency). This means that 1 Euro can be exchangeable to 1.25 US Dollars. The most traded currency pairs in the world are called the "Majors". They involve the currencies euro, US dollar, Japanese yen, pound sterling, Australian dollar, Canadian dollar, and the Swiss franc. Currency quotations use the abbreviations for currencies
World currency a single world currency is unnecessary, because the U.S. dollar is providing many of the benefits of a world currency while avoiding some of the costs. If the world does not form an optimum currency area, then it would be economically inefficient for the world to share one currency. In the present world, nations are not able to work together closely enough to be able to produce and support a common currency. There has to be a high level of trust between different countries before a true world currency could be created. A world currency might even undermine national sovereignty