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The Dow Jones Industrial Average (DJIA) is one of the world's oldest stock market indexes, consisting of 30 US corporate giants.
Despite some criticism, the Dow remains highly respected, a reliable gauge of the overall stock market and the US economy.
While you can't invest in the DJIA itself, you can buy an index fund that tracks it, or the individual stocks.
When people talk about "the Dow," "the Dow Jones," or "the Dow 30," they're referring to the Dow Jones Industrial Average (DJIA). And to understand the Dow, you must understand it's actually two things: a stock market index of 30 chosen companies and a benchmark number.