An index fund is a type of mutual fund with a portfolio constructed to match or track the components of a market index, such as the Standard & Poor's 500 Index (S&P 500). An index mutual fund is said to provide broad market exposure, low operating expenses and low portfolio turnover.  Other indexes include.

Russell 2000 (small companies), DJ Wilshire 5000 (total stock market), MSCI EAFE (foreign stocks in Europe, Australasia, Far East), Lehman Aggregate Bond Index (total bond market)."