Europe is in trouble. Big trouble. That's likely what's been causing fireworks in our stock market lately. If Greece and a few others default, a slew of European banks that hold those countries' bonds will be thrown into woe. Once a country's banking system is in distress, the rest of its economy suffers, exacerbating its sovereign debt problems. It's a vicious cycle that America is painfully aware of after our own -- albeit very different -- financial crisis in 2008.

American banks like JPMorgan Chase (NYSE: JPM), Citigroup (NYSE: C), and Bank of America (NYSE: BAC) have, by and large, insisted that their exposure to Europe isn't threatening. Federal Reserve chief Ben Bernanke said last week that American banks' European exposure is "manageable relative to their capital" -- a nice response, even if it's one he's obligated to give lest he cause a panic. Since so much of the financial system is opaque -- and, more importantly, built on confidence -- no one can say what might happen. Warren Buffett's quip that "It's only when the tide goes out that you learn who's been swimming naked" seems relevant here.

What should you make of it all? I recommend five articles that may help you better understand what's going on.

Fool contributor Morgan Houselowns B of A preferred. Follow him on Twitter @TMFHousel. The Motley Fool owns shares of Bank of America, Citigroup, and JPMorgan Chase. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.