First there was one. CBOE (or Chicago Board Options Exchange) may no longer be the only options exchange, but it's still the US leader in overall volume. Founded in 1973 by the Chicago Board of Trade (now part of CME Group), CBOE lists options on more than 1,900 stocks, as well as on interest rates, broad-based stock indexes (such as Standard & Poor's S&P 500 Index), and industry indexes. CBOE, which had already launched the fully electronic CBOE Futures Exchange, debuted its CBOE Stock Exchange in early 2007, going head-to-head with the NYSE and NASDAQ. CBOE also runs The Options Institute, which provides training for brokers and investors. CBOE raised $339 million in a 2010 initial public offering (IPO).