SYSTEM is a pattern formed by waterbodies in the AREA including rivers and their tributaries, lakes etc. It is governed by the topography of the land and HARDNESS of the rock.A drainage system can be classified based on Catchment Area, ORIENTATION to sea, Place of Origin.According to the origin, the drainage system in India is classified in to:Himalayan (Perennial Rivers): Indus, GANGA, Brahmputra and their tributaries.Peninsular(Non-Perennial Rivers): Narmada, Tapi, Mahanadi, Godavari, Krishna, Cauvery and their tributaries.