The line between proprietary trading, an activity that has fueled an unprecedented expansion of the global financial markets in recent years, and plain old gambling is not always clear.
And when the bets go bad, everyone suffers.
Now, lawmakers are debating a measure that would limit the amount of risky trading regular commercial banks are allowed to do. The regulatory implications are far-reaching, and have unsettled investors worldwide.
To understand the proposal and its potential impact, Need to Know spoke with Felix Salmon, a financial blogger for Reuters. He recently received the 2010 Excellence in Statistical Reporting Award from the American Statistical Association.