A stock index is a collection of stocks intended to be reflective of the stock market as a whole or, in some cases, a particular industry or segment of the market. In other words, a stock index ...

An index fund is a mutual fund or ETF composed to match the composition of a benchmark stock index and mirror its performance. For example, The Vanguard Russel 2000 ETF is composed of the same ...

Index funds are mutual funds that seek only to mirror the performance of an underlying stock market index — not to outperform ...