Sutras are written down words spoken by the Buddha Shakyamuni, narrated by his disciples. Sutra texts comprise the foundation of the textual canon of all Buddhist traditions. Sutras generally begin with the words, “Thus have I heard,” and continue to describe the place, time, and context in which the Buddha gave the teaching. Important Mahayana sutras include the Avatamsaka Sutra and the Prajnaparamita Sutras, as well as many others. Other important types of Buddhist text are avadanas, dharanis, as well as tantras.