Orangutan, meaning "old man of the forest" in Malay, currently only inhabit the islands of Sumatra and Borneo.   It is these two geographical locations that help differentiate between the two species.  Pongo pygmaeus abelii, the Sumatran Orangutan and Pongo pygmaeus pygmaeus the Bornean Orangutan.   Fossil evidence indicates that their past distribution included much of Southeast Asia.

     Orangutans are normally only found in forested areas.  Their preference for forests is wide spread and can contain multiple types of forestation from low-level swamps to mountainous areas, tropical rainforest and tropical deciduous forests.

     The Borneo male have large distinguished cheek pads, a tremendous laryngeal sac and a square shaped face. Sumatran males do not have the protruding cheek pads and are often characterized by a ginger colored mustache and a diamond shaped face. Orangutan males are approximately twice the size of females, weighing between 165 and  220 lbs. and reaching a height of 5 ft. Females reach a weight average of 90 lbs. The laryngeal sac, when inflated, increases the resonance and   tone of the male Orangutan voice, producing the commonly noted "long call".  This "long call" sounds like a loud roar and plays an important role in repelling male rivals and in advertising their availability to sexually receptive females. Orangutan's posses long narrow hands and feet which are suitable for grasping branches.  The arms of an Orangutan have been known to span upwards of eight feet across.  The thumb and big toe are short to facilitate the hook-like function of the hands and feet in these modified brachiators. The legs of an Orangutan are considered week in respect to the strength possessed within their arms.  Orangutans, as with many primates, have an opposable thumb. Orangutans, unlike Gorilla and Chimpanzee, move by fist walking when on the ground.  An Orangutan's coat is normally a deep reddish-brown and shaggy but often thin in quantity.