Buddhism began with the experience of one person during a time of religious ferment in India during the fifth century B.C.E. Born the son of a prince in what is now Nepal, Siddhartha Gautama forsook the life of a noble to seek spiritual answers to life's deepest questions, especially those concerning the profound suffering and eventual death all people experience. After much seeking and studying, Siddhartha had an enlightenment experience while meditating and took as his name the Buddha, the awakened one. He spent the rest of his life traveling to teach his insights and way of life.

His teachings were both practical and profound. He advocated a "middle path" between a worldly life and the extreme asceticism popular among religious seekers in India. He organized his teachings as the Four Noble Truths, which taught how to minimize suffering and attain inner peace. The First Noble Truth explored the reality and depth of suffering. The Second Noble Truth related suffering to desires or wants that were insatiable. The Third Noble Truth maintained that suffering could be eliminated by removing desire. The Fourth Noble Truth described how this could be done by following a path with eight aspects centering around the three main goals of seeing life objectively, living kindly and ethically, and cultivating inner peace through mental discipline and meditation. Contained in his teaching was the insight that the world is in constant change. Everything is made up of parts, and both the things and their parts are in such constant change that nothing, including personal identity, has permanence.

As a reformer, the Buddha rejected many aspects of the Hinduism of his day. These included the caste system, an emphasis on ritualism, elaborate metaphysical philosophizing, and belief in a permanent spiritual reality. He accepted ideas on karma and rebirth and the notion of liberation, which he called nirvana. In the centuries after his death, several schools emerged that eventually crystallized into the great branches of Buddhism recognized today: Theravada, Mahayana, and Vajrayana.

Theravada is the only surviving conservative school whose goal was to pass on the Buddha's teachings unchanged. Theravada Buddhism centers on the interdependence of the community of monks with the laity. Monks pursue nirvana supported by the laity, who gain merit by providing them with food, clothing, and provisions for the monastic life. Monks, in turn, are role models who offer advice, and run schools, meditation centers, and medical clinics.

The Mahayana branch subdivided into many different schools and introduced innovations in philosophy and practice. The Mahayana ideal was the deeply compassionate person called a bodhisattva, who refused to fully enter nirvana to help others end their suffering. The historical Buddha was deemphasized in many schools by a worldview that saw the universe populated by many Buddhas and bodhisattvas. Major schools include Shingon, Tendai, Pure Land, Nichiren, and Zen.

Vajrayana is associated with Tibetan Buddhism that combines Mahayana principles with various esoteric practices incorporating mantras, mudras, and mandalas. An interesting feature is the transmission of leadership through reincarnations of other lamas.

Buddhism reached the West in four historic waves of influence. Perhaps now it is evolving a fourth branch blending core Buddhist insights and practices with Western ideals.