A market index of approximately 6,500 U.S. based equities traded on the American Stock Exchange, the New York Stock Exchange and the NASDAQ stock market.
Equity: In a margin account, this is the difference between the securities owned and the margin loans owed. It is the amount the investor would keep after all positions have been closed and all margin loans paid off.
Index: A compilation of the prices of several common entities (stocks) into a single number. An index is a group of stocks which can be traded as one portfolio, such as the S&P 500. Broad-based indexes cover a wide range of industries and companies and narrow-based indexes cover stocks in one industry or economic sector.