What's the difference between a mutual fund and a unit investment trust? With a mutual fund, its manager invests in assets according to a stated set of objectives. Shares are issued and redeemed on demand at a specific net asset value that is determined at the end of each trading day (based on the total market value of the fund's holdings). There's no fixed number of shares. If many people want to buy in, the fund company will issue more shares.

Meanwhile, a unit investment trust (UIT) invests in a relatively fixed portfolio of investments. These are held until the trust is liquidated at a predetermined date in the future. Investors who want to trade shares of a UIT before it matures can often do so on the secondary market. Unlike a mutual fund, UIT share prices in the secondary market may be priced above or below the net asset value of the trust's actual holdings. When you buy shares of UITs, you typically pay a sales fee, or load, of around 4% or 5%; many mutual funds carry no sales load at all. That's generally a not-so-good thing.

To learn much more about mutual funds, poke around our rich and informative Mutual Funds Center. If you'd like to learn about particularly promising top-notch funds, grab a free sample of our Champion Funds newsletter.

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