Dandruff is a common scalp condition characterized by the shedding of dead skin cells. It often appears as white or yellow flakes on the scalp and hair, and can sometimes cause itching. Dandruff can be caused by various factors, including dry skin, sensitivity to hair products, or a yeast-like fungus called Malassezia. While dandruff is not contagious and usually not serious, it can be bothersome. Over-the-counter shampoos containing ingredients like zinc pyrithione, salicylic acid, or ketoconazole can help manage the condition. Maintaining a healthy scalp through regular washing and moisturizing can also reduce dandruff symptoms.