Basal cell carcinoma

Note the raised lesion like a volcano. It looks like a hill with a depression at its peak. they usually arise above a line joining the angle of the mouth to the ear lobule. To differentiate it from benign lesions - note the lines of skin - they are lost over the BCC lesion but are preserved over the benign lesions.
On the other hand, a squamous cell cancer looks like a flat lesion that is necrotic in the center. Melanomas are wholly black and thus not a problem to differentiate and for them one better get going and get it excised and sent for Histology ASAP.
All 3 of these skin cancers are predisposed to by sun exposure.
This lesion will be treated with surgical excision and sent for histologic confirmation to see that the borders are free of the malignancy.

This particular patient had multiple Solar keratoses too and they would be treated with 5FU cream and Cryosurgery.