Jaundice is a condition where the skin, tissues in the body, mucus membranes in the mouth & whites of the eyes appear yellowish. This is caused by a substance known as bilirubin, a yellow pigment that is produced when newborn bodies work to eliminate the extra red blood cells they are naturally born with. Your baby's body will dispense with the bilirubin naturally through stool and urine, and jaundice will go away in several days.
You can assist with this process by feeding your baby more frequently. Occasionally, a doctor will place babies under special lights(phototherapy), or lay them on a special fiber optic blanket to help.