An exchange traded fund (ETF) is a type of fund that is traded intra-day on an exchange. Examples include index ETFs and closed-end ETFs. Usually people use the term closed-end funds, but they are a type of exchange-traded fund. An exchange traded fund (ETF) is a type of fund that is traded intra-day on an exchange. Examples include index ETFs and closed-end ETFs. Usually people use the term closed-end funds, but they are a type of exchange-traded fund.