Pranayam is largely considered as an exercise to extend the life force (prana). It is the perfect control of the life-currents through control of breath, and is the process by which we understand the secret of prana and manipulate it.

'Prana' has a broad number of meanings, few of them are,
1. Breath / respiration,
2. the breath of life / vital air / principle of life,
3. Energy
4. The spirit or soul

Yoga is a way of living. Yoga is not only a exercise but it also helps to lead a good and healthy life, making you look good and stay happy.