Skin cancer is a type of cancer that forms in the tissues of the skin due to excessive exposure to sunlight.
Risk factors. It is more common among people who spend time in the sun, have suffered burns and those who have light skin, hair and eyes.
Prevention. Prolonged sun exposure damages the skin. Sunlight causes damage through ultraviolet (UV) rays.
In any case, remember that the sun is not the only cause of skin cancer and that it can be found on parts of the body that have never been exposed to the sun.
Treatment. You should consult your doctor if you notice a spot or mole has changed in shape, size and/or colour, it becomes painful or you have a skin lesion that has recently appeared and is growing.
There are several types of skin cancer. Skin cancer that forms in melanocytes (skin cells that produce pigment) is called melanoma and is the most dangerous. Approximately 65% to 90% of melanomas are caused by exposure to ultraviolet (UV) light.
Skin cancer that forms on the inside of the epidermis (outer skin layer) is called basal cell carcinoma. Skin cancer that forms in squamous cells (flat cells that form the surface of the skin) is called squamous cell carcinoma.
The two most common types of skin cancer, basal cell carcinoma and squamous cell carcinoma, are highly curable.
For more information visit:
Melanoma Skin Cancer Overview
http://www.cancer.org/cancer/skincancer-melanoma/overviewguide/
Skin Cancer: Basal and Squamous Cell Overview
http://www.cancer.org/cancer/skincancer-basalandsquamouscell/overviewguide/
Digestive 
Blood
Cardiovascular
Dermatology
Genitourinary,
Hormones
Infections
Oncology and
Musculo-skeletal
Mental health and
Parasites
Respiratory
Senses
Various
