Theravada ("Way of the Elders") the single remaining representative of the eighteen (or twenty) Nikaya Schools of Indian Buddhism. Due to errors in early Buddhist scholarship, it sometimes mistakenly associated with the term Hinayana. This school is now most common in Sri Lanka, Burma, Thailand, Cambodia, Laos and Indochina.
Sarvastivadin One of the main branches of Indian Abhidharma that was instrumental in the creation of Yogacara doctrine. It's system of monastic rules Vinaya is still used in the Gelukpa school of Tibetan Buddhism.