A friction ridge is most commonly known as the skin that is found on the palms of the hands and the bottoms of the feet. Fingerprints are another name for a friction ridge.
This type of skin is corrugated, which means it features tiny furrows between ridges. These ridges provide friction that helps the hands and fingers grip objects. These ridges also provide the feet with a stable surface to walk without slipping and sliding on smooth surfaces. Fingerprints are useful in investigations, such as those by the police or other law enforcement officials, to provide identification to an individual. These ridges are unique to every person and are permanent.