<Ul> <Li> Sūtra: prose discourses, especially short declarative discourses . </Li> <Li> Geya: mixed prose and verse discourse . Identified with the Sagāthāvagga of the Saṁyutta Nikāya </Li> <Li> Vyākarana: explanation, analysis . Discourses in question and answer format . </Li> <Li> Gāthā: verse </Li> <Li> Udāna: inspired speech </Li> <Li> Ityukta: beginning with' thus has the Bhagavan said' </Li> <Li> Jātaka: story of previous life </Li> <Li> Abhutadharma: concerning wonders and miraculous events </Li> <Li> Vaipulya either' extended discourses' or' those giving joy' (cf Mahayana Texts) </Li> <Li> Nidāna: in which the teachings are set within their circumstances of origin </Li> <Li> Avadāna: tales of exploits </Li> <Li> Upadesha: defined and considered instructions </Li> </Ul> <Li> Sūtra: prose discourses, especially short declarative discourses . </Li> <Li> Geya: mixed prose and verse discourse . Identified with the Sagāthāvagga of the Saṁyutta Nikāya </Li> <Li> Vyākarana: explanation, analysis . Discourses in question and answer format . </Li>

The main teaching of buddha are compiled in which book