Melanoma is a type of skin cancer that begins in melanocytes, the cells that produce melanin, which gives skin its color. It typically appears as a new spot or a change in an existing mole. Melanoma can occur anywhere on the skin, but it's most common in areas exposed to the sun. Risk factors include fair skin, excessive sun exposure, a history of sunburns, and a family history of melanoma. Early detection is crucial for successful treatment. Treatment options include surgery, immunotherapy, targeted therapy, chemotherapy, and radiation therapy. Prevention strategies include sun protection measures like wearing sunscreen and protective clothing.