A market-capitalization weighted index of the more than 3,000 common equities listed on the Nasdaq stock exchange. The types of securities in the index include American depositary receipts, common stocks, real estate investment trusts (REITs) and tracking stocks. The index includes all Nasdaq listed stocks that are not derivatives, preferred shares, funds, exchange-traded funds (ETFs) or debentures. Taobiz explains Nasdaq Composite Index Unlike other market indexes, the Nasdaq composite is not limited to companies that have U.S. headquarters. It is very common to hear the closing price of the Nasdaq Composite Index reported in the financial press, or as part of the evening news.