A quick summary of skin damage due to the sun.
Solar hyperkeratosis.......commonest cause by far....Google it
Bowen's disease....not malignant and very common.......Google it.
Basal Cell Carcinoma...........doesn't metastasize....cure rate 100%
Squamous Cell Carcinoma.......rarely metastasizes.....cure rate 90%
Malignant melanoma.....the most uncommon of the skin cancers.....not a nice one to have......big debate as to whether it has ANY connection with sun exposure.
sqad's potted version.