Hong Kong Monetary Authority

So you know how sometimes you save up some money in a piggy bank or a jar, and you use that money to buy things that you want or need?
Well, think of Hong Kong Monetary Authority like a big piggy bank for all of Hong Kong's money. They help make sure that the money is safe and that it's being used the right way.
They also set rules and guidelines for the banks in Hong Kong to follow, to make sure they're doing their jobs correctly and safely too.
Basically, they're like the grown-up who watches over all the money in Hong Kong and makes sure everything is okay.