Mutual funds are investment vehicles that pool money from many investors to purchase a diversified portfolio of stocks, bonds, or other securities. They offer individual investors access to professionally managed portfolios and can be an effective way to diversify investment risk. Mutual funds are categorized based on the types of investments they hold, their objectives and the returns they seek, with options ranging from aggressive growth funds to conservative fixed-income funds. It's important for investors to consider the fund's objectives, goals and risk when making investment decisions.