The other night me and my grandma were sitting at dinner talking and I decided to ask her "what caused the Great depression?" And she didnt know, she said "well the stock markets crashed" so I asked "why?" and she said "well money had no value" and I said "but why? What caused it?"
Ultimately it had never been explained to either of us so for the purpose of educating my already very clever readers....
The answer is the leaders in countries with the most influence were having a problem with deflation (money wasnt worth anything) and they in turn used solutions that would work on inflation to try and solve this problem. Most americans (or at least I didnt) dont realize the great depression was worldwide.
So to compress it down more, alotta really "smart" ppl had a whole string of bad ideas which ultimately lead up to the stock market crashing, banks folding, and ten years of turmoil.
Luckily we came out of it, and eventually someone had a bright idea to network computers which eventually snowballed into the idea of wikipedia, which happens to be where I got my information. :)