Dark circles are a common skin condition characterized by a darker pigmentation under the eyes. They can result from various factors, including lack of sleep, stress, and genetics. The skin in this area is thinner, making blood vessels more visible, which contributes to the appearance of dark circles. Other causes may include aging, allergies, and dehydration. While dark circles are usually not a serious health concern, they can affect one's appearance and self-esteem. Treatments often involve lifestyle changes, such as improving sleep quality, and topical creams that may help reduce pigmentation and puffiness.