People have been growing citrus fruits for thousands of years. The first mentions of these plants have been found in Chinese manuscripts from about. 2200 B.C. Today citrus fruits can be found almost all over the world. Apart from the fact that people eat them in a raw form, citrus fruits serve also a decorative function, they are used for curing numerous diseases (e.g. cancers) and they are used in food and cosmetic industries, due to essential oils that occur in them.