Passive investing is a method in which an investor aims to equal the success of a stock market index rather than beating it all through active stock buying and selling. This is often accomplished by purchasing index funds or exchange-traded funds (ETFs) that track a certain market index. The theory underlying passive investing is that the stock market, on average, produces a high rate of return over time, and that many professional investors struggle to exceed the market. As a result, passive investors are more concerned with attaining market returns at a reduced cost, with much less time and money focused on company selection and timing the market.