What caused the 2008 financial and housing crisis in the USA and how did it affect Europe and the rest of the world?

I would like to understand what happened during the 2008 global financial crisis. What caused the housing market in the United States to collapse and why did it trigger such a massive economic crisis? What were subprime mortgages and how did complex financial products like mortgage-backed securities and credit default swaps turn a housing bubble into a global catastrophe? Which major banks and financial institutions collapsed or had to be rescued and why did governments spend billions of taxpayer money to bail them out? How did a crisis that started in the American housing market spread so quickly to Europe and the rest of the world? What was the impact on ordinary people, including job losses, home repossessions, and cuts to public services? How did different countries in Europe respond and recover at different speeds, including the eurozone debt crisis that followed in Greece, Ireland, Spain, and Portugal? What lasting changes did the 2008 crisis bring to banking regulation and financial oversight? And what lessons did the world learn, or fail to learn, from it?