What does a bank do with your money?
Once again there are tremors rumbling through the banking industry. Bank collapses, takeovers and rescue packages are back in the news, and all this got us wondering: Where is my money?
This quick explainer explores the surprisingly ancient history of banks to see how they evolved, looking into just how much of your money your bank actually has and why it's such a big problem when everyone wants their money back at the same time.
Video by Dan John
Additional images and footage: BBC News, Getty Images and Alamy