The document discusses two major stock indices in India - S&P BSE Sensex and CNX Nifty. Sensex was launched in 1986 and is calculated based on the free float market capitalization of 30 stocks. It is a market-weighted index with its base year as 1978-79 and base value of 100. Nifty is also a major stock index introduced by NSE, consisting of 50 stocks selected using the same methodology as Sensex. It has a base year of 1995 and base value of 1000. Both indices are important indicators that represent the overall Indian stock market.