Can countries print extra money whenever they wish to bail themselves out of a financial crisis or do they need to secure the amount to be printed by depositing the equivalent in gold at a safe place like Fort Knox?

I asked the same Question to Someone once, and there answer was

If they do do that, then their mony becomes more wortheless to other countries.
So I don't think they would want to do that!

This is an awesoem question and I hope someone has a better answer!