Coconut itself is a seed. The fruit is ovoid or nearly ovoid, with a triangular top and a length of about 15-25 cm. Exocarp thin, mesocarp thick and fibrous, endocarp hard. There are three holes in the base, one of which is opposite to the embryo, and the other two holes are relatively firm. The fruit cavity contains endosperm (namely "pulp" or kernel), embryo and juice (coconut water). Anyone who has eaten coconut knows that the peel of coconut is divided into three layers, the outer layer is thin and smooth, the texture is dense and the water resistance is good. The middle layer is thick and loose, full of air and light, floating on the water; The inner layer is a hard core of white coconut meat and sweet coconut water. They provide sufficient nutrients for the growth and development of seeds, and then the seeds of coconut trees are inside. Therefore, coconut trees have a strong floating ability, and they can often drift in the sea for several months, and then settle down on a suitable coast, sprout and take root, blossom and bear fruit, and reproduce. This may explain why most coconut groves grow on beaches.