During this period, many schools of Buddhism arose, the two best known being Theravada and Mahayana. Theravada, considered to be the original teaching, is practised widely in Sri Lanka, Thailand, Burma, Cambodia and Laos, while Mahayana is found mostly in China, Japan and Korea. A further form of Buddhism, known as Vajrayana, is practised in Tibet. The actual practice of the teachings differ widely among the various schools, with much emphasis on ritual in some of them. He could see with his new-found wisdom that all beings in the universe are subject to certain natural laws and that they are trapped in an endless sequence of existences.
Death is just one phase of the cycle, which is followed by rebirth.
The Buddha was able to perceive how beings passed from one existence to another, and how their circumstances changed in accordance with their deeds. He saw that all these existences, both the happy and unhappy periods, were of a temporary nature and subject to perpetual change. In the ancient Pali language, in which the word of the Buddha is preserved, this unsatisfactory and uncertain state of affairs is termed Dukkha loosely translated as 'suffering'. According to the Buddha, all existence in the universe, including living beings, is in a state of flux or change. All sentient beings are subject to a cycle of birth, growth, decay and death.