This document defines key terms related to income from business and profession under the Income Tax Act of 1961 in India. It states that business means any economic activity carried out for earning profits, including trade, commerce, or manufacture. A profession is an occupation requiring intellectual or manual skill, such as law, accounting, engineering, medicine, or authorship. Income from business and profession must be carried out by the assessee in the previous year and includes losses. Illegal businesses are still taxable.