Stock indexes are collections of stocks meant to represent the market or a portion of it—they are used by investors as benchmarks against which to compare the performance of their own portfolios.

While stock market indexes may most often come to mind, indexes are also constructed around other asset classes. In the bond market, for example, the Bloomberg Aggregate Bond Index tracks the ...

can be a good representation of the overall U.S. stock market. Other indexes have more specific characteristics that create a more narrowly targeted market focus. For example, indexes can ...

The days of the star stock-picking portfolio manager are largely behind investors, with a few exceptions. For years, passive index funds have dominated the mutual fund and exchange-traded fund ...

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 ...

Some stock market indexes are designed to provide a measure of the broader market's performance, like tracking a sample of large companies across sectors. And some stock market indexes have a ...

Image source: Getty Images. Indexes can also be useful for measuring the performance of your own portfolio against a benchmark. For example, if your stock portfolio drops by 7% in a certain month ...