An Exchange Traded Fund is essentially a basket of stocks that reflects the composition of an Index, like the Sensex or the Nifty. The price of the ETF reflects the net asset value of the basket of stocks. Exchange Traded Funds (ETFs) are are listed and traded on exchanges like stocks. There are various categories of ETFs in India. They are:-

• Equity
• Gold
• World Indices
• Debt

While an ETF is similar to a mutual fund in many ways, there are crucial differences between ETFs and mutual funds.

• Unlike a mutual fund, where NAV is calculated at the end of the day, the price of the ETF changes real time throughout the day, based on the actual share prices of the underlying stocks at any point of time during the day

• Mutual funds are actively managed, whereas ETFs are passively managed. Mutual funds aim to generate an alpha (or outperformance versus a market benchmark), whereas ETFs aim to track a particular index

• Mutual funds have specific investment objectives, like capital appreciation, income generation, large cap stock focus, midcap stock focus, sector focus etc. ETFs only aim to track the relevant index and reduce tracking errors

• Even though mutual funds aim to diversify unsystematic risks (or security specific risk), and they do diversify, to a large extent, there is likely to be still some residual unsystematic risk in mutual funds because mutual funds do not exactly reflect the market portfolio. ETFs, on the other hand, are only subject to systematic risk (or market risk), since they reflect the market portfolio

You need to have a demat account to invest in ETFs. On the other hand, you do not necessarily need to have a demat account to invest in mutual funds How to purchase / buy / invest in mutual funds?.