What is the benefit of owning a mutual fund.?

please be detailed, include costs and who should be interested.

The benefits are to make money, or to keep from losing money.

A mutual fund is a form of investment where the fund owns many different stocks in different companies. You as an investor don't own the stock directly - you own shares of the fund. The fund company does the accounting, deciding when to buy and sell stocks, record keeping, etc. They get paid by keeping a percent of the money you send in.

Say you send in $100 each month. The fund company keeps some of it - say $1, or 1% - and uses the other $99 to buy stock. If the stock they own goes up in value, your share in the fund goes up. If the stock goes down, your share goes down. Some funds charge very little for expenses - like 1/2%. Others charge more, maybe 2 or even 3%. This is important; if the stock market goes up 10% in a year, but your mutual fund goes up only 7%, and they charged you 3%, you've only made maybe 4% instead of what you might have made somewhere else.

Also - different funds have different goals. Some are higher in risk, some invest in only certain market sectors - tech, transportation, foreign, and so on. Before you invest, you should learn more about this, and get the prospectus from any fund you're interested in. Read it, study it, and learn what it's talking about. It's your money - you might as well be in charge of it.

diversification of assets is the key. Professional management also of value though Index funds cheaper. Everyone should be interested. Costs vary all over the place from .25% of assets in an etf or spartan fund up to 2% + of assets in a high yield bond or emerging markets fund. There are all types of funds & so there is at least 1 (really more) you should own. Never too early to start investing.

The only benefit to owning a mutual fund (and it's not much of a benefit) is that it releases you from the obligation of doing your homework.

Those of us that actually want to MAKE money would never touch a mutual fund.