Sangha

 Sangha  is community of Buddhists. Used to mean monastic community but concept broadened. Showing the path to enlightenment.

About 100 years after Buddha's death, communities disagreed and split over ways to achieve enlightenment. Traditional school of Theravada Buddhists follows Buddha's original teachings. Mahayana school accepts some changes, various ways to enlightenment (became Zen).

Scripts appeared also introducing changes. Deification of Buddha, and separation between mortal Buddha like Siddharta who will reappear, and transcendental ones which are only understood through meditation (Dhyani Buddhas). While enlightenment reached through individual effort, idea spread that meditation Buddhas give merit to those who worship them. Bodhisattvas are humans who reached enlightenment but instead of joining nirvana chose to help others reach enlightenment.