What kind of language is Shauraseni Prakrit
Shauraseni Prakrit was a Middle Indo-Aryan language and a Dramatic Prakrit. Shauraseni was the chief language used in drama in medieval northern India. Most of the material in this language originates from the 3rd to 10th centuries, though it was probably a spoken vernacular around the 2nd century BCE in the ancient state of Surasena. 

Among the Prakrits, Shauraseni is said to be the one most closely related to Classical Sanskrit in that it is derived from the Old Indian Indo-Aryan dialect of the Madhyadesa on which Classical Sanskrit was mainly based. Its descendants include the languages of the Hindi Belt, the Central Zone of modern Indo-Aryan or Hindi languages, the standard registers of the Hindustani language based on the Delhi dialect.