Collectively, exchange-traded funds, or ETFs, are doubling assets every couple of years. In order to achieve a feat like that in finance you need some attractive qualities. The ETF happens to have many. You can almost think of these as a disruptive technology, akin to the MP3 or Uber. They’re at once fast, good, and cheap—and few things combine all three of those ingredients for consumers. 

On the first episode of Bloomberg's new podcast, Trillions, we break down in plain English what exactly makes ETFs so powerful and popular, including their low-cost, diversification, liquidity, convenience, and transparency. Together, these elements are why ETFs are democratizing investing. And they’re not done transforming the investment industry yet, either. In fact, two evolutionary lines are already forming. In one, fees are plummeting toward zero; in the other, every “active” strategy and theme you can think of is getting repackaged as an ETF.