In contrast ot consonants, where voice, manner and place of articulation serve as descriptive categories, vowels are differentiated by their position of the tongue and the lips. The positioning of the tongue and the lips allows for a great amount of variation, enabling us to voice many more vowels than the familiar five vowels [a, e, i, o, u]. It was pointed out that vowels can be produced by raising the tongue high, keeping it in the middle, or low in the mouth.