Dandruff is scientifically known as seborrheic dermatitis. It is a chronic inflammation of the scalp that causes flaking, resulting in the usual white or yellowish flakes that accumulate in the hair and on clothing. Depending on the characteristics of the flaking and the level of oiliness, the condition is clinically divided into two main types: Oily Dandruff (or seborrheic dermatitis): Characterized by thicker, yellowish, and sticky flakes that stick to the hair and scalp, often accompanied by itching and redness. Dry Dandruff: Characterized by thin, loose, white scales that fall easily onto the shoulders.