The Nātya Shastra is an ancient Indian treatise on the performing arts, encompassing theatre, dance and music. It was written at an uncertain date in classical India (between 200 BCE and 200 CE). The Natya Shastra is based upon the much older Natya Veda which contained 36,000 slokas (; ). Unfortunately there are no surviving copies of the Natya Veda. There are scholars who believe that it may have been written by various authors at different times. The most authoritative commentary on the "Natya Shastra" is "Abhinavabharati" by Abhinava Gupta .