World leaders are meeting in Cannes in France to discuss what can be done to solve Europe's money problems. But why is Greece at the centre of it all?
Greece has borrowed loads of money over the last 10 years or so - both from European banks and from other countries' governments.
It used the money to run the country, pay for the 2004 Olympic Games and also for things like big pay rises for people who are paid by the government.
But when you borrow money, you have to pay it back, with what's called 'interest' - meaning you pay back more money than you borrowed to begin with.
Then in 2008, the whole world was hit by a banking crisis where all the world's banks were worried they wouldn't get their money back.
The cost of borrowing from banks went up hugely - and Greece had borrowed and spent so much that it couldn't afford to repay its debts.
Greece isn't alone though - all countries borrow money, and Portugal, Spain, Italy and Ireland are all really badly in debt, too.
Watch the clip to see business reporter Steph McGovern explain more to Sonali.