According to Wikipedia: ‘In Buddhism, the sūtra refers mostly to canonical scriptures, many of which are regarded as records of the oral teachings of Gautama Buddha. In Chinese, these are known as jīng. These teachings are assembled in part of the Tripitaka which is called Sutra Pitaka. There are also some Buddhist texts, such as the Platform Sutra, that are called sūtras despite being attributed to much later authors.’