Skin cancer is a type of cancer that starts in the skin cells. The three most common types of skin cancer are basal cell carcinoma, squamous cell carcinoma, and melanoma. Basal cell carcinoma and squamous cell carcinoma are the most common types and are usually curable if detected and treated early. Melanoma is less common but is more likely to spread to other parts of the body and can be deadly if not caught and treated early. Risk factors for skin cancer include exposure to ultraviolet (UV) radiation from the sun or tanning beds, having fair skin, a history of sunburns, a weakened immune system, and a family history of skin cancer. Prevention measures include protecting the skin from UV radiation by wearing protective clothing, using sunscreen with a high SPF, and avoiding tanning beds. It is important to check the skin regularly for any unusual moles or growths and to see a doctor if anything suspicious is found. Treatment options for skin cancer depend on the type, location, and stage of the cancer but may include surgery, radiation therapy, chemotherapy, or immunotherapy.