This document discusses different skin conditions including dermatitis, eczema, erythroderma, leukoderma, vitiligo, and onychomycosis. Dermatitis is inflammation of the skin, while eczema is a form of dermatitis. Erythroderma causes red skin and leukoderma causes white skin, also known as vitiligo. Melanocytes in the basal layer produce melanin and can accumulate. Onychomycosis is a nail fungus condition.