Psoriasis is a chronic inflammatory skin disease characterized by thick red patches covered with silvery scales. It occurs when skin cells replicate too quickly, causing a buildup on the skin's surface. The causes are genetic and can be aggravated by stress, alcohol, and smoking. There are several types including plaque, guttate, pustular, and nail psoriasis. Treatment involves topical creams and drugs to reduce inflammation and rapid cell turnover, as well as phototherapy. Nursing care focuses on skin protection, education, and promoting self-acceptance of the condition.