You might hear about the Dow a lot, but odds are, you're not entirely aware of which companies make up the Dow -- more formally known as the Dow Jones Industrial Average. Many people don't realize it, but the Dow is merely an average based on the stock prices of 30 companies. Out of thousands and thousands of existing companies, just 30 make up the Dow. Here's the current list:

Alcoa (NYSE:AA)
Altria (NYSE:MO)
AmericanExpress (NYSE:AXP)
Boeing (NYSE:BA)
Caterpillar (NYSE:CAT)
Citigroup (NYSE:C)
Coca-Cola (NYSE:KO)
Disney (NYSE:DIS)
DuPont (NYSE:DD)
ExxonMobil (NYSE:XOM)
General Electric (NYSE:GE)
General Motors (NYSE:GM)
Hewlett-Packard (NYSE:HPQ)
Home Depot (NYSE:HD)
Honeywell (NYSE:HON)
Johnson & Johnson (NYSE:JNJ)
JPMorgan Chase (NYSE:JPM)
McDonald's (NYSE:MCD)
Merck (NYSE:MRK)
Microsoft (NASDAQ:MSFT)
MinnesotaMining & Manufacturing(3M) (NYSE:MMM)
Pfizer (NYSE:PFE)
Procter & Gamble (NYSE:PG)
SBC Communications (NYSE:SBC)
United Technologies (NYSE:UTX)
Verizon (NYSE:VZ)
Wal-Mart Stores (NYSE:WMT)

The list could change at any time, but it doesn't change too often. The last time it changed was actually fairly recently -- in April 2004 -- and Bill Mann recapped the switcheroos. The list above may remain correct for years.

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