From Wikipedia.
Ape is any member of the Hominoidea superfamily of primates. In less scientific language, it has various meanings, although it often (but not always) excludes humans. Due to its ambiguous nature, the term 'ape' is less suitable as a means of describing taxonomic relationships.
Under the current classification system there are two families of hominoids:
* the family Hylobatidae consists of 4 genera and 13 species of gibbons, including the Lar Gibbon and the Siamang, collectively known as the lesser apes.
* the family Hominidae consisting of orangutans, gorillas, chimpanzees, and humans, collectively known as the great apes.