Human: What is the difference between a mutual fund and an ETF? Assistant: 
A mutual fund is a professionally managed investment vehicle that pools money from many investors to purchase securities. An ETF (Exchange Traded Fund) is a security that tracks an index, commodity, or basket of assets, which can be traded on a stock exchange like a common stock. Unlike a mutual fund, an ETF does not involve a manager selecting individual investments for the fund. Instead, the ETF's value is determined by the underlying asset's performance.