Simultaneously with the practice of asanas, there should be effort towards the regulation of the prana. So, asana and pranayama go together. There is an intimate relation between the activity of the physical body and that of the prana. The prana is the total energy which pervades the entire physical system and acts as a medium between the body and mind. The prana is subtler than the body but grosser than the mind. The prana can act but cannot think. The prana is not merely the breath. The breathing process-inhalation, exhalation and retention-does not constitute the prana by itself, but is an indication that the prana is working. We cannot see the prana; it is not any physical object. When we breathe out, the prana operates in one of its functional forms. When we breathe in, the apana functions. The book "Pranayama: Introduction and Practices" includes four chapters namely Concepts of Prana in first Chapter, Second Chapter include Concept of Pranayama, Third Chapter explored Types of Pranayama, Mind, and Soul, Fourth Chapter explored Questions and Answers and last chapter included Glossary. References and Poses of Pranayama have been given in the last part of the book.