The NASDAQ Stock Market, also known as the NASDAQ, is an American stock exchange. "NASDAQ" originally stood for "National Association of Securities Dealers Automated Quotations," but the exchange's official stance is that the acronym is obsolete. It is the largest electronic screen-based equity securities trading market in the United States and fourth largest by market capitalization in the world. With approximately 3,700 companies and corporations, it has more trading volume than any other stock exchange in the world. When the NASDAQ stock exchange began trading on February 8, 1971, the NASDAQ was the world's first electronic stock market. At first, it was merely a computer bulletin board system and did not actually connect buyers and sellers. The NASDAQ helped lower the spread (the difference between the bid price and the ask price of the stock) but somewhat paradoxically was unpopular among brokerages because they made much of their money on the spread.