A stock index is a basket of stocks that helps investors keep track of the market, its fluctuations and its trends. 

The S&P 500, Dow Jones Industrial Average (DJIA), and Russell 2000 are some of the popular indices financial experts are looking at to get a gauge of the markets.

Watch below NYSE floor trader Jonathan Corpina, a senior managing partner at Meridian Equity Partners, Inc., explain how indices work and what the key differences between major indices are:


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Produced by Daniel Goodman