Learn how index funds invest in market indexes like the S&P 500 for broad diversification and market performance replication.

What is an index? It’s hard to say these days. An index used to be a broad measure of market value. Today, it appears to mean any list of securities that are configured and managed in any way. This ...

Index funds are mutual funds that seek only to mirror the performance of an underlying stock market index — not to outperform it. Millions of investors hold them in their portfolios because they ...