The Dow Jones Industrial Average (DJIA) was first published in 1896 and tracks 30 of the largest U.S. listed companies.
Along with the S&P 500, the DJIA is a primary benchmark for the US stock market. It's a price-weighted index so higher priced companies have a larger impact on the index movement.
As at April 2016, it accounted for around 25% of US equity market capitalisation.
Constituents can be drawn from either the New York Stock Exchange (NYSE) or the NASDAQ Exchange.