Moles are flat or raised, usually pigmented, growth on the skin or just underneath the skin. There are several different types of moles with only some that carry an increased risk of skin cancer. Moles have a variety of different appearances and colors ranging from red to brown-black. A mole is concerning for cancer if it is a new mole, or an old mole that has developed suspicious characteristics. These characteristics include asymmetry, irregular borders, multiple colors in one mole, and size greater than pencil eraser (5mm).