However, mutual funds control risk to some extent because they are diversified. That means they invest in a large number of investments at the same time spreading out the impact if any one of the investments should lose money. For example, if the fund held stocks in 30 companies and one company went out of business, the loss of the value of that stock would not make the fund collapse as there are 29 other companies that are still doing fine and growing. You must also realize there is the risk of taking no risk. If you invest in cash, inflation can eat away at your purchasing power.
Inflation is how much the cost of goods increases over time.
When you put money into a savings account you are receiving a very low rate of interest. The bank uses your money to lend to other customers, charging a higher rate of interest. The difference between those two rates is how the bank makes money. The value of your account never goes down and it only goes up with the payment of interest. You are being paid back for the risk you are willing to take by investing in a variety of companies.