Skin cancer — the abnormal growth of skin cells — most often develops on skin exposed to the sun, but it also can occur on areas of skin not ordinarily exposed to sunlight. Skin cancer is the most common form of cancer in the U.S.

"And the incidence of skin cancer is rising," says Dr. Dawn Davis, a Mayo Clinic dermatologist.

The three major types of skin cancer are basal cell carcinoma, squamous cell carcinoma and melanoma. Early detection of skin cancer gives you the best chance for successful skin cancer treatment.

While it is common to have freckles and moles develop over time, it is important to know your skin and recognize when changes occur.

"It's important to know what skin lesions you have," explains Dr. Davis. "Know what they look like, so that if they change, you can come to the dermatologist or health care provider for evaluation."

Melanoma is the most serious and deadly form of skin cancer. Dr. Davis says the "melanoma alphabet" can help with early detection:

On the Mayo Clinic Q&A podcast, Dr. Davis discusses skin cancer detection and treatment. Dr. Davis also recommends steps to take to protect your skin including avoiding ultraviolet rays, and wearing sunscreen and protective clothing.