What is the Dow Jones Industrial Average?

Well... it's not a mediocre floor cleaner for manufacturing plants.

What it is is the oldest and most quoted market indicator in the United States and the world. It consists of only THIRTY stocks! Most people would consider these "blue chip" stocks.

The DJIA was first published in 1896 during the Industrial Revolution. Initially, it was all industrial companies--hence the name "industrial average." But, over the years, the shift has been made to service companies like Microsoft, Disney, Coca-Cola, and McDonald's.

So, when we talk about the Dow Jones, and it only consists of 30 stocks in a market containing more than 7,000 stocks, how important is this index?