In this Act, unless the context otherwise requires,-

(i) Sales tax law means any law for the time being in force in any State or part thereof which provides for the levy of taxes on the sale or purchase of goods generally or on any specified goods expressly mentioned in that behalf and includes value added tax law, and "general sales tax law" means any law for the time being in force in any State or part thereof which provides for the levy of tax on the sale or purchase of goods generally and includes value added tax law;