These two ETFs have similar investment styles, but there are some key differences.The Nasdaq has been the biggest driver of stock market returns for over a decade. The tech-heavy Nasdaq Composite index has produced annualized returns of more than 16% over the past 10 years, significantly outpacing the benchmark S&P 500.There are two main indices that track the performance of the Nasdaq: the Nasdaq 100 and the Nasdaq Composite. And two great index funds that you can use to invest in these are the Invesco QQQ ...