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Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Wall Street Crash of 1929

So, while doing some personal research on the Great Depression, I realized that I can't wrap my head about the Wall Street crash. Especially since I don't know a think about economics, stocks and such. So explain to me like I am 5 the Crash fo 1929?

Thanks.


EDIT: Thank you all so much for explaining!
gpt
You have money. And you want to invest them in stocks. You do, and stocks do well, so you sell them to get your money back plus some more.

Rise and repeat.

Now what happens when you take a bank loan. And use that money to invest in stocks. Because you think that you can invest money you don't really have, do well, make a profit and pay the bank back while keeping the extra for yourself.

What happens when hundreds of thousands of people do that?

The market gets flooded with money that doesn't exist. There was no actual backing to it. And what happens when stocks don't do well. People couldn't pay the banks back.

How do banks do loans? Well they borrow other people's money to give to one person. When that person pays back the bank, that money goes back to the original owners. Because at one time, people just have their money sit in the bank. And so the bank makes a profit by lending out other people's money because they know they'll get it back. (Either by having people pay back the loan or foreclosing on their houses and selling the house...and stuff like that) And it becomes a cycle of borrowing.

So, now the bank has given out too many loans to people who invested their non-existent money to make a profit that didn't happen. 

And you think "why doesn't the bank foreclose on houses and repossess those people's things."
They could but it would have been pointless.
Houses and cars had to be repossessed by the companies that had sold them on credit. Except the companies did not want them because there warehouses were already full with brand new appliances and cars ready to be sold. The loan agencies did not want the houses because they had no one to sell them to. 

People tried to take their money out of the bank when the stock market crashed but found that there was barely any money in there. It was all loaned out. And those loans were sucked up by bad investments.

So everyone ended up poor. And poor people can't buy new or used things. So the cycle continued as factories and stores shut down because nobody was buying their products. Nobody was investing in them.