Accountancy, or accounting, is the systematic process of recording, analyzing, and reporting financial transactions of a business or organization. It provides accurate financial information for internal management, external stakeholders, and taxation purposes. 

Business refers to an organized entity or enterprise engaged in commercial, industrial, or professional activities with the primary objective of generating profits. It involves the production, sale, or provision of goods and services to customers in exchange for monetary compensation. 

Management is the process of planning, organizing, coordinating, and controlling resources and activities within an organization to achieve predetermined goals. It involves decision-making, resource allocation, and leadership to ensure effective and efficient outcomes. The key functions of management include planning, organizing, coordinating, controlling, and leading.