Article 1 of the KSA Value Added Tax Law establishes the foundational definitions for terms used throughout the legislation. It specifically defines 'Authority' as the General Authority of Zakat and Tax and 'Law' as the Value Added Tax Law itself. Other key definitions include 'Agreement' (the Unified GCC VAT Agreement), 'Kingdom' (the territory of Saudi Arabia), and 'Regulations' (the implementing regulations). The article also clarifies the meaning of 'Output Tax' as the tax due on a taxable supply, and 'Tax Invoice' as a document issued for such supplies. For any terms not defined herein, their meanings are to be derived from the Unified VAT Agreement.