The NASDAQ-100 is a stock market index made up of 107 equity securities issued by 100 of the largest non-financial companies listed on the NASDAQ. It is a modified capitalization-weighted index. The stocks' weights in the index are based on their market capitalizations, with certain rules capping the influence of the largest components. It is based on exchange, and it is not an index of U.S.-based companies. It does not have any financial companies, since these were put in a separate index. Both of those criteria differentiate it from the Dow Jones Industrial Average, and the exclusion of financial companies distinguishes it from the S&P 500.