The Buddha — the "Awakened One" — called the religion he founded Dhamma-vinaya — "the doctrine and discipline." To provide a social structure supportive of the practice of Dhamma-vinaya (or Dhamma for short [Sanskrit: Dharma]), and to preserve these teachings for posterity, the Buddha established the order of bhikkhus (monks) and bhikkhunis (nuns) — the Sangha — which continues to this day to pass his teachings on to subsequent generations of laypeople and monastics, alike.

As the Dhamma continued its spread across India after the Buddha's passing, differing interpretations of the original teachings arose, which led to schisms within the Sangha and the emergence of as many as eighteen distinct sects of Buddhism.[3] One of these schools eventually gave rise to a reform movement that called itself Mahayana (the "Greater Vehicle")[4] and that referred to the other schools disparagingly as Hinayana (the "Lesser Vehicle"). What we call Theravada today is the sole survivor of those early non-Mahayana schools.[5] To avoid the pejorative tone implied by the terms Hinayana and Mahayana, it is common today to use more neutral language to distinguish between these two main branches of Buddhism. Because Theravada historically dominated southern Asia, it is sometimes called "Southern" Buddhism, while Mahayana, which migrated northwards from India into China, Tibet, Japan, and Korea, is known as "Northern" Buddhism.[6]