The way people throw around the words “Dow” and “Nasdaq” makes them seem synonymous with “the market.” But there are important differences.The Dow refers to the Dow Jones Industrial Average, which is a key index that indicates how the stock market is performing. The Nasdaq can refer to the National Association of Securities Dealers Automated Quotations System, which is a global electronic marketplace where investors buy and sell securities. It can also refer to the Nasdaq Composite Index, which measures the performance of a portion of the stock market, as well. The Dow and the Nasdaq both refer to an index, or an average that’s calculated from the performance of certain stocks. The Dow tracks stocks from 30 of the biggest companies in their respective industries, most of which trade on the New York Stock Exchange. The Nasdaq tracks about 4,000 stocks that are listed on the Nasdaq exchange. Investors cannot trade the Dow or Nasdaq, but they can buy index funds or ETFs that track either one.