The most fundamental Buddhist holy book is called the Tripitaka (or "Tipitaka" in the ancient Indian language of Pali in which it was originally written). The Tripitaka is an extensive text, comprising three large volumes, or baskets, referring to the way in which sewn-together collections of inscribed leaves were stored at the time of its compilation.
The first of these baskets ("pitakas") is known as the "vinaya," or "discipline" basket. It contains more than 200 regulations and codes of conduct for Buddhist monks and nuns, covering both moral issues and practical advice, such as socializing with the general public or making a robe.
The second basket, the "sutra" or "discourse" pitaka, contains the teachings and discourses of the Buddha, including his allegorical anecdotes and proscriptions for enlightenment. It also expands on issues of moral conduct.
The third basket is called the "abhidarma pitaka" and contains a combination of stories, songs, poetry and, in the Dharmapada, Buddhist conceptual theory.
While this is the earliest and most important Buddhist scripture, ultimately deferred to by followers in all three of the major schools of Buddhism (Theravada, Mahayana and Vajrayana), some schools supplement it with other texts. Mahayana and Theravada Buddhists, for example, also base their tradition on the Sutras, and the Lotus Sutra in particular, as well as the teachings of the Buddhist philosopher Nagarjuna.