The euro is a type of money that is used by 16 countries in Europe.
The notes and coins were introduced in January 2002, when 12 countries started to use them instead of their own currencies, like the French Franc and Italian Lira.
Euroland, or the eurozone, is what people call the European Union countries who use the euro.
Which countries use it?
At the moment the United Kingdom does not use the euro. If it is brought in to replace pounds and pence it would be after a long and important discussion.
The government has said that the UK economy must pass a number of important tests before the politicians will think about joining the euro.
If the UK does pass those tests then it's thought everyone in the country who is allowed to vote will help decide if the UK joins up.
There will probably be a huge vote called a referendum to decide if the pound will be replaced by the euro.