it means if u go to greece, u don't have greece currency 2 bring back 2 show or collect. if u go to estonia, italy, uk, anywhere in europe, there's only one currency: euro. which is great in its ideal.
egin, there's always a country or two that will vie for domination but if they're not too pushy, & there's always room to butt heads(not killing competitions here), it's ok. after all, humans being imperfect, any invention or thoughts or ideas that we come up with will be imperfect at best as well.