Dark discoloration of the skin under the eye is mainly referred to as dark circles. It is also known as dark rings or shadows. Some of the main causes behind the formation of dark circles are heredity, aging, dry skin, prolonged crying, working for long hours in front of a computer, mental or physical stress, lack of sleep and an unhealthy diet.Both men and women of different age groups can have dark circles. Dark circles are not a serious skin problem, but they make people look tired, exhausted, unhealthy and older. You can easily get rid of unsightly shadows under your eyes using some easy home remedies.