Egregoros

What actually happened in 2008? (I was young)

From what I loosely gather (heard, not claim), it was something about mortgage loans lended to applicants who couldn't afford them or mortgage interest rates suddenly rising on already established homeowners (I'm not sure how that one would be, unless mortgages weren't at fixed rates).

I really don't know because "explanatory" (exculpatory) articles play hot potato and shrug, and I wasn't old enough at the time.

Anyone here know?