The Standard & Poor’s 500 (S&P 500) is a market weighted index of 500 widely held stocks selected to be representative of the stock market as a whole.
The S&P 500 is a popular stock market index and as such the S&P 500 is often used as a barometer of the US stock market as a whole.
Related Terms: Capitalization-Weighted Index – Dow Jones Industrial Average (DJIA) – Price-Weighted Index – Dow Divisor – Common Stocks