Mutual Funds can either be open-ended or close-ended funds.  Most are open-ended funds. Here are the primary features of both:

• A fund that continually creates new shares on demand (although the manager can close it if they think the fund is getting too big).
• You can purchase the shares at Net Asset Value (NAV) (see above).  You can redeem them (sell) at any time at the value of the NAV directly from the fund.
• Usually trades at the end of the market day.
• It may or may not have a sales commission attached to it.

• A fund that has a fixed number of shares.
• Usually listed on the stock exchange.  You can actively buy or sell them.
• Since its shares are traded on the market, they can be traded any time during the market day.
• Since it is a stock, it always has a commission associated with it.