Kurzgesagt - In a Nutshell 2015 Episode 3 Banking Explained β Money and Credit ( Air Date 2015-03-12 ) Genre Documentary category. Overview "Banks are a riddle wrapped up in an enigma. We all kind of know that they do stuff with money we donβt understand, while the last crisis left a feeling of deep mistrust and confusion. We try to shed a bit of light onto the banking system. Why were banks invented, why did they cause the last crisis and are there alternatives?".