Final answer:
Melanoma is the most dangerous form of skin cancer characterized by black or dark brown patches on the skin that appear uneven, jagged, or raised.
Step-by-step explanation:
Melanoma is the most dangerous form of skin cancer. It is often characterized by black or dark brown patches on the skin that appear uneven in texture, jagged, or raised. Melanoma is highly metastatic and can be difficult to detect before it has spread to other organs. Treatment typically involves surgical excision and immunotherapy.