Definitions in GST law set supply, registration, turnover and input tax rules that govern tax incidence and compliance. Section 2 supplies the definitive terminology for the Rajasthan GST regime, defining who and what the Act governs, including broad definitions of business, categories of persons (taxable, registered, casual, non-resident), and places of business and fixed establishments. It sets out supply-related constructs such as taxable supply, outward and inward supply, reverse charge, and distinguishes composite and mixed supply. Fiscal bases and compliance mechanisms-aggregate turnover, input tax, input tax credit, electronic ledgers and documentary instruments-are defined, and numerous terms are cross referenced to central GST and related statutes to ensure consistent interpretation.