An open-end mutual fund is a type of investment fund that allows investors to buy and sell shares essentially at any time. This type of fund does not limit the number of shares that can be issued, and its price is regularly updated based on the fund's asset value, usually at the end of the trading day. Open-end mutual funds provide investors with flexibility, liquidity, and access to a diversified portfolio of various investments. They are managed by professional fund managers who are responsible for the investment strategy and asset selection.