There are four common mutual funds in the United States: stock funds, bond funds, hybrid funds and money market funds.

It is very convenient to buy the share of * * * with the fund. Investors (investors outside the retirement fund plan) can purchase funds through professional investors (such as brokers, financial analysts, bank representatives, insurance agents) or directly according to their own research and understanding. Professional investors provide services for investors, including: analyzing customers' needs and goals, and recommending appropriate fund varieties. They need to be paid for these services, which are generally deducted from the fund assets in the form of service fees. Diversified investment fund managers usually invest in a variety of stocks to diversify their portfolios. A diversified portfolio is conducive to reducing risks (the rise of some share prices in the portfolio makes up for the decline of some share prices to some extent). It is usually difficult for ordinary investors to build a diversified portfolio like a fund. * * * The same fund provides ordinary investors with decentralized portfolio investment opportunities managed by experts that only large institutions can do.