Apples, which grow on trees, are a member of the rose family. The outer skin can be various shades of red, green and yellow. The bitter taste of an apple's seeds makes them inedible. It takes an apple tree four to five years to produce fruit.
Apples are low in calories; an average size apple contains 50 calories. Apples are rich in antioxidants and dietary fiber and do not contain any saturated fat. They are a good source of vitamin C and B-complex vitamins. A large percentage of an apple's fiber and antioxidants are found in the peel.
Of the 7,500 varieties of apples in the world, 2,500 are grown in the United States. With hundreds of varieties of apples grown for commercial use, the United States is one of the world's leading producers of apples, along with China, Turkey, Poland and India. Apples were a popular food in both ancient Greek and Roman culture.
The first apple tree planted in the United States was planted in the Massachusetts Bay Colony by the Pilgrims. As of 2015, apples are grown in each of the 50 states. The first apple nursery in the United States opened in 1730, in Flushing, New York. Popular types of apples include Golden delicious, Fuji, gala, Granny Smith and winesap.