Nifty 50 index is a collection of 50 blue-chip companies listed on the National Stock Exchange of India (NSE). These companies are selected based on various criteria, such as market capitalization, liquidity, and financial performance, and are considered to be representative of the overall performance of the Indian stock market.

50 companies listed on NSE based on free-float market capitalization are part of Nifty 50.

The top three sectors of Nifty 50 index are Banks with weightage of 12.00%, IT - Software with 12.00%, Automobile with 12.00%.

The Nifty 50 is weighted on the free-float market capitalization wherein the level of the index reflects the total market value of all the of 50 listed stocks in the index, relative to the base period of 3 November, 1995.

You can invest in Nifty 50 index by investing in ETFs that follow this index. Top three ETFs that follow Nifty 50 index are Kotak Nifty 50 ETF, LIC Nomura MF ETF - NIFTY 50 - Growth Plan and Indiabulls Nifty50 ETF.