Psoriasis typically presents with symmetrically distributed, red, scaly plaques with well-defined edges. The scale is often silvery white, except in skin folds where plaques may appear shiny with a moist peeling surface. Common sites include the scalp, elbows, and knees, though any part of the skin can be affected. Symptoms may include mild to severe itching, painful skin cracks or fissures, and the Koebner phenomenon, where new lesions form on previously damaged or irritated skin. Upon healing, plaques may leave postinflammatory hypo- or hyperpigmentation that fades over time.