Check out this article about the newest type of ETF. Exchange Traded Funds have grown exponentially in popularity over the last decade. Investors like them because they can trade them like individual stocks, but they offer the same diversification as a mutual fund. Although, these funds have typically followed an index like the S&P 500 instead of being actively managed by a fund manager.
Now, a new breed of ETF’s is putting in the human element of managing funds. An ETF provided lower fees, because you weren’t paying for a broker’s commission or fees, but now brokers like Vanguard and Fidelity and put their hot hands on an ETF and still charge a lower fee than the traditional mutual fund.