"As a result of this request, Buddha rose from meditation and taught the first Wheel of Dharma. These teachings which include the Sutra of the Four Noble Truths and other discourses, are the principal source of the Hinayana, or Lesser Vehicle, of Buddhism.

Later, Buddha taught the second and third Wheels of Dharma, which include the Perfection of Wisdom Sutras and the Sutra Discriminating the Intention respectively. These teachings are the source of the Mahayana, or Great Vehicle, of Buddhism.

In the Hinayana teachings Buddha explains how to attain liberation from suffering for oneself alone, and in the Mahayana teachings he explains how to attain full enlightenment, or Buddhahood, for the sake of others.

Both traditions flourished in Asia, at first in India and then gradually in other surrounding countries, including Tibet. Now they are also beginning to flourish in the West."
Introduction to Buddhism by Geshe Kelsang Gyatso