Citrus fruits are a group of fruits that belong to the Rutaceae family, which includes oranges, lemons, limes, grapefruits, and tangerines. They are typically round or oblong in shape, have a thick rind, and are characterized by their acidic, juicy pulp. Citrus fruits are a good source of vitamins and are used in a variety of culinary applications, such as juices, salads, and desserts.