The most common form of psoriasis is plaque psoriasis, which accounts for about 87% of cases. It is characterized by silvery, dry scales and severe itching on the scalp and other parts of the body. Other types include erythrodermic psoriasis, which presents as red, scaly patches; guttate psoriasis, marked by small, droplet-like patches, often seen in children and young adults; pustular psoriasis, which features pus-filled blisters; and flexural, palm, and sole psoriasis, which affect specific areas of the body.