Melanoma, the most serious type of skin cancer, form in the cells(melanocytes) that makes melanin,the pigment thag gives skin its colour.The exact cause of all melanomas is not clear but exposure to ultra violet light and sunlamps may increase the risk of getting this. Credits: https://www.instagram.com/p/CPEqZ7uB2gY/?utm_medium=copy_link
So check your whole body skin atleast once per month &any change in color or size of nevus should be seen by a dermatologist