There is a kind of disease almost everyone has, no matter you are handsome handsome man, or beautiful beauty are no exception. This disease is the color nevus, the scientific name of pigmented nevus, nevus cell nevus, Chinese medicine known as “black”, commonly known as “nevus”, “black mark”, “black nevus “Moles are the most common type of nevus in Chinese medicine. Almost everyone has a nevus, but there are fewer of them in infancy and early childhood, and they gradually increase after puberty. The size, number, color, shape, and location of moles are very different for each person. The small ones are like sesame seeds, green beans or even smaller, while the big ones can cover a limb or a large piece of torso; the small ones are just a few, a dozen or a handful, while the large ones are hundreds or thousands, which are countless, and there are about forty to fifty moles for each person on average. The color of nevus is most common in black-brown, brown, blue, red, white (anemic nevus), etc.; the shape of nevus is mostly round, oval, but also irregular or strange, most of the surface is elevated, smooth, and hairless, but also the surface is wrinkled as wart-like, rough and uneven with a lot of hair, known as the “animal skin nevus”. Moles can grow on the skin and mucous membranes of the whole body, but they are most common on the head, face, neck, and the ends of the limbs, while moles can grow on the eyes, nose, mouth, finger nails, and toe nails, etc. Moles can be said to be ubiquitous. The occurrence of pigmented nevus originates from the developmental abnormality in human embryonic period, and has certain heredity; pigmented nevus is usually divided into two categories: congenital and acquired. Congenital nevus is present at birth and gradually increases in size with age, and those with a diameter greater than 250px are called congenital giant nevi. It is reported that this type of nevus has a malignant rate of about 10%. Acquired nevus appears after birth, mostly occurs in children and adolescence, especially grows rapidly after adolescence, and stops growing in adulthood, and becomes lighter in color, smaller and softer in size in old age. In addition, nevus pigmentosus is related to ultraviolet radiation. In summer, the color of nevus pigmentosus deepens and its shape increases after being exposed to sunlight due to the increase of outdoor activities, and the color decreases in winter. Nevus pigmentosus belongs to benign tumors, most of them will not be malignant and have no conscious symptoms, so they do not affect your health and do not need to be treated. However, there are very few moles that turn into malignant melanoma, which is life-threatening.