Orange trees are widely grown in tropical and subtropical climates for their sweet fruit. The fruit of the orange tree can be eaten fresh, or processed for its juice or fragrant peel. The fruit of the Citrus sinensis is considered a sweet orange, whereas the fruit of the Citrus aurantium is considered a bitter orange. The orange is a hybrid, possibly between pomelo (Citrus maxima) and mandarin (Citrus reticulata), which has been cultivated since ancient times.