This document provides an overview of input tax credit (ITC) under the Goods and Services Tax (GST) in India. It defines ITC as the tax paid on purchases that can be reduced from output tax payable on sales. It outlines the key conditions for claiming ITC such as being GST registered, having a valid invoice, goods/services received, and supplier paying tax. It also discusses documents needed for ITC, time limits, reversal of credit, special cases, ineligible items, and refund of ITC. The document is intended to help explain the important rules and mechanisms around ITC under GST.