Vernacular Sanskrit is rather cover term for a whole range of linguistic phenomena. Under this cover term, we can discuss linguistic varieties of many different kinds. Sanskrit in the ancient Vedic corpus shows signs of regional and social dialects, some signs of women's usage, as well some signs of interaction with local Indo-Aryan or Non-IE languages. The question of what is standard and non-standard Sanskrit has been discussed by Sanskrit grammarians and the discussion shows interesting sociolinguistic layers in the usage, not all considered acceptable by the grammarians. In later times, varieties of Sanskrit called Budhist Hybrid Sanskrit, Jaina Hybrid Sanskrit, Inscriptional Hybrid Sanskrit, etc. become available to us showing a range of Sanskritized vernaculars and vernacularized Sanskrit. Finally, as we come to more recent times, there is a range of evidence demonstrating effects of various types of interaction between Sanskrit and the local vernaculars, resulting in features of usage that violate the rule of the grammarians, and yet make Sanskrit more deeply embedded in the world of vernacular users and listeners.