Originally, the word was used to identify oral teachings thought to have been given directly by Siddhartha Gautama (Buddha) around 600 B.C. Sutra is a Sanskrit word meaning "thread" and is synonymous with Pali, the religious language of Buddhism.
Sutras are records of teachings given by the historical Buddha, Shakyamuni. The Buddha’s discourses were memorized by his disciples and later written down in various languages, the most complete collections of teachings being in Pali and Sanskrit. Because sutras contain the actual words spoken by Buddha, by reproducing that speech ourselves during recitations our voice becomes a conduit for the spread of Buddha’s teachings in the world.