Dow Theory

Dow Theory
A theory which says the market is in an upward trend if one of its averages (industrial or transportation) advances above a previous important high, it is accompanied or followed by a similar advance in the other.
The theory also says that when both averages dip below previous important lows, it's regarded as an indicator of a downward trend.
Dogs Of The Dow
An investing strategy that consists of buying the 10 DJIA stocks with the highest dividend yield at the beginning of the year. The portfolio should be adjusted at the beginning of each year to include the 10 highest yielding stocks.
The strategy was formulated in 1972 and has proven to be successful. In fact, as Dog of the Dow investors readjust their portfolios each year, it places pressure on the stocks involved.
Dow Jones Industrial Average - DJIA
The Dow Jones Industrial Average is a price-weighted average of 30 significant stocks traded on the New York Stock Exchange and the Nasdaq. The DJIA was invented by Charles Dow back in 1896.
Often referred to as "the Dow", the DJIA is the oldest and single most watched index in the world. The DJIA includes companies like General Electric, Disney, Exxon and Microsoft. When the TV networks say "the market is up today", they are generally referring to the Dow.
Theoretical Dow Jones Index
A method of calculating a Dow Jones index (most often the DJIA) that assumes all index components hit their high or low at the same time during the day.
In other words, the "theoretical Dow" uses the daily highs for all 30 Dow components to calculate the index high, and the lows to calculate the index low. In January of 1992, Dow Jones started using the "actual" method, which calculates the index at 10-second intervals throughout the day. Before this point, the theoretical calculation was the only way to compute the high and low of the index. This method assumes that all stocks hit their high or low at the same time. Because this rarely happens, the theoretical high will almost always be higher than the actual, and the theoretical low will almost always be lower than the actual.
Who or what is Dow Jones?
Dow Jones, or more precisely "Dow Jones & Company", is one of the largest business and financial news companies in the world. The firm was founded in 1896 by Charles Dow, Edward T. Jones and Charles Bergstresser. In 1889 they founded The Wall Street Journal, which remains one of the most influential financial publications. It is easy to confuse Dow Jones with the Dow Jones Industrial Average (DJIA). Often referred to as "the Dow", the DJIA is one of the most watched stock indexes in the world, containing companies like General Electric, Microsoft, Coca-Cola and Exxon. Dow Jones (the company) owns the Dow Jones Industrial Average as well as many other indexes that represent different sectors of the economy. In the world of finance, you'll often hear people ask, "How did New York do today?" or "How did the market perform today?" In both cases, these people are likely referring to the DJIA as it is the most widely used index, above both the S&P 500 Index and the Nasdaq Composite Index.