Buddha-nature (Skt. buddhata); according to the Mahāyāna view, the true, immutable, and eternal nature of all beings. Since all beings possess this buddha-nature, it is possible for them to attain enlightenment and become a buddha, regardless of what level of existence they occupy.
The interpretation of the essence of buddha nature varies from school to school; there is controversy over whether all beings and also inanimate entities actually possess buddha nature.
The answer to the question whether buddha-nature is immanent in beings is an essential determining factor for the association of a given school with Hīnayāna or Mahāyāna, the two great currents within Buddhism. In Hīnayāna this notion is un known; here the potential to become a buddha is not ascribed to every being. By contrast the Mahāyāna sees the attainment of buddhahood as the highest goal; it can be attained through the inherent buddha-nature of every being through appropriate spiritual practice.
Source: The Encyclopedia of Eastern Philosophy and Religion: Buddhism, Hinduism, Taoism, Zen. Shambhala Publications, Inc.
Books on Buddha-nature
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