Moles occur when cells in the skin grow in a cluster instead of being spread throughout the skin. These cells are called melanocytes, and they make the pigment that gives skin its natural color. Moles may darken after exposure to the sun, during the teen years, and during pregnancy.
Skin tag is a small flap of tissue that hangs off the skin by a connecting stalk. Skin tags are not dangerous. They are usually found on the neck, chest, back, armpits, under the breasts, or in the groin area. Skin tags appear most often in women, especially with weight gain, and in elderly people.
A wart is a skin growth caused by some types of the virus called the human papillomavirus (HPV). HPV infects the top layer of skin, usually entering the body in an area of broken skin. The virus causes the top layer of skin to grow rapidly, forming a wart.