This document discusses the five heads of income under the Indian Income Tax Act: (1) income from salaries, (2) income from house property, (3) profits and gains from business or profession, (4) capital gains, and (5) income from other sources. It provides an overview of the types of income included in each head and how they are taxed, such as salary and allowances being included in income from salaries and the different methods of computing capital gains on long-term versus short-term assets. The document also explains how gross total income is calculated by adding income from all five heads and how total income is determined by making deductions from gross total income.