Billy - "Yea woteva man lets go play computer games"
Coins in the currency are marked on one side with a representation of Europe (or the globe on copper coins) and on the obverse with a national design that varies between countries and often between denominations within a country; all versions are of course legal tender within the Euro zone. 1, 2 and 5 cent coins are of copper plated steel. 10, 20 and 50 cent coins are of an alloy known as Nordic Gold for its colour but in fact are gold free. 1 Euro coins have are two-toned, with a cupronickel centre and a surrounding nickel brass ring, a design reversed on the 2 Euro coin.
Bank notes are standardised across the Euro zone and feature representations of different styles of windows and bridges symbolic of the openness of the unifying European culture, with more modern architectural styles represented on higher denomination notes.
The Euro started off within a cent of parity with the US dollar; the exchange rate at the time of writing is approaching one Euro to one US dollar and fifty cents. Various countries in the Far East have expressed a preference for the Euro over the dollar as a unit of international currency.
As of submission, €1 = approximately $1.50
Trade and import-export transactions within Europe and with other nations is much easier.
No more national currencies in the eurozone saves quite a bit of money for consumers and travelers, as well as businesses which engage in a high degree of cross-border business.
The pooled European capital of the euro currency has created a strong world reserve currency that could not have been achieved with the previous national currencies.
German (and to a lesser extent French) taxpayers find themselves perpetually bailing out countries with dysfunctional economies. See Greek Debt Crisis.
Not all nations in the Eurozone are equally wealthy or in a position to maintain healthy debt-to-GDP ratios over long periods. The interest rates set by the ECB are often favorable for wealthier eurozone countries but not for poorer ones. While some less-wealthy countries can't survive without a default, other less-wealthy countries muddle along with unhealthy but sort of manageable debt levels. The euro is not necessarily good for these countries, as they can't periodically devalue currency to improve their trade. Then again, their ability to trade without the losses of currency conversion highlights the benefits of a common currency.
Q: But the Grexit forced the thing below six dollars! A: that's capitalism and money for you :-p