Sanskrit is an ancient language of India and a source of later languages & literature across the world. The first-ever book of the world, Rigveda, was compiled in Sanskrit. The body of Sanskrit literature encompasses a rich tradition of poetry and drama as well as scientific, technical, philosophical, and religious texts. Most transmissions of knowledge were oral and as gurukul systems and the guru-shishya tradition collapsed, that knowledge has been irretrievably lost, which includes many branches (shakhas) of sacred texts (shastras), Vedas and Vedangas included. Sanskrit continues to be widely used as a ceremonial language in Hindu religious rituals and Buddhist practices in the form of hymns and chants.