Classification system used for mutual funds to help investors identify important information about the mutual funds. With this system, investors can quickly identify the fee structure based on the letter assigned to each mutual fund. For example, Class A shares require that the investor pay a fee upfront and is considered a front-end load fund. Class B shares do not require a fee to be paid up front, but do require that a fee be paid after the sale of the fund. This type of fund is considered a back-load fund. Mutual fund share classes are widely used in print publications such as newspapers.