There are many types such as atopic dermatitis, contact dermatitis, seborrheic dermatitis, stasis dermatitis, dyshidrotic dermatitis, and nummular dermatitis. Although symptoms are similar, each type has characteristic features. Atopic dermatitis, contact dermatitis and seborrheic dermatitis are considered common in the general population, and contact dermatitis is associated with occupational skin disease.