The Buddhist path is traditionally divided into three yanas or vehicles: Hinaya, Mahayana and Vajrayana.
The Hinaya shcools, of which only Theravada remains, focuses primarily on the discourses of Shakyamuni Buddha, including his guidance to develop meditative awareness and to cease all negative emotions and actions that bind us, lifetime after lifetime, to this suffering existence called samsara.
Mahayana included much of what is taught in Hinayana, but it emphasizes the altruistic motivation for practitioners to attain complete enlightenment in order to save all sentient beings from suffering.
The third vehicle, Vajrayana or tantra, means “continuum” of “unbroken stream” from ignorance to enlightenment. Vajrayana is a continuation of Hinayana and Mahayana and has been passed through initiations from masters to disciples.
IN TIBETAN BUDDHISM, ALL THREE VEHICLES BECOME A SINGLE PATH