What caused the Great Depression and the current recession in the United States today?

Economic recessions are said to be caused by a decline in GDP growth, which is caused by a slowdown in manufacturing orders, falling housing prices and sales, and a drop-off in business investment. This leads to unemployment and a slow down in sales. Ten years ago, there was an economic boom but eventually the demand for products decreased and stock prices did too and companies went bankrupt. In spite of this stock market decline, interest rates rose. Interest rates were high when the economy needed low rates for loans and mortgages. A cause of the current recession is that the interest rates weren't raised when the economy started to boom again. This caused people to buy homes they couldn't afford or to just resell homes they just bought. In 2006, the higher rates started to kick in, the prices of houses declined and they were selling their homes for less then their mortgage, many faced foreclosure. This caused banks to panic and realize they were facing huge losses. Later next year the banks were afraid to lend to each other and this led to the $700 billion bailout. In 1929 the stock market crash on Black Tuesday coincided with the Great Depression. Stockholders lost billions of dollars in the following months and even though the stock market began to regain some of its losses, it still wasn't enough to escape the Great Depression. Another factor was bank failures. People lost their savings from the failing banks and the banks that stayed open were less willing to provide loans. This lead to less expenditure from the American people. People were losing their jobs and the unemployment rate rose above 25%. Both of these economic situations have to do with a decrease in consuming and banks not offering loans when the economy desperately needs to consume. The great depression ended because of WWII and demand of goods and jobs that came with the war. What is going to get us out of this recession we are in today?