This chart is a roadmap of "The Shadow Banking System". It was created by economists at the New York Federal Reserve, and I learned about it from an article by Gillian Tett in the Financial Times.
My picture of the map is hard to read here, but it does convey how complicated finance has become. The top section (down to the gold band) is the "traditional banking system". But that's a relatively small part of it. The remainder consists of the "cash" and "synthetic" shadow banking systems, or "financial intermediaries".
The NY Fed's research paper is well worth reading too - you can find it here.