By measuring the compilation of similar stocks instead of just one or two stocks, a stock index provides information about that particular market or segment. One of the most talked about and popular indexes is The Dow Jones Industrial Average (DJIA) which consists of 30 of the biggest companies in the U.S.
Stock indices are typically related by some commonality: for example, the Dow Jones Wilshire 5000 is an index that measures or tracks almost every publicly traded stock in the United States. The Morgan Stanley Biotech Index is a small index that follows the biotechnology market. Each stock index has a specific focus that can provide highly specific or very generalized information.
Interested in learning more? Explore new stock market indexes such as: Ethical Stock Market Indexes and Environmental Stock Market Indexes.