The meaning of Chakras

I am not an expert on the chakra system, but the more I delve into pranayama, the more I learn about the chakras, bandhas and nadis. 
The word chakra means "wheel" or "ring" in Sanskrit.  In B.K.S. Iyengar's book, Yoga: The Path to Holistic Health, he says each personal chakra has energy coiled within them.  The main chakras align the spine from the tailbone to the brain and are critical junctions that determine the state of the body and mind. 
Mr. Iyengar writes that, "yogic science recognized this connection from the very beginning.  In order to achieve  perfect physical health, the ancient sages concluded, you must activate the body's chakras."  Chakras are complex and difficult to explain as they are not composed of matter but relate to our body's subtle levels, which include our prana (life force) and consciousness (citta). Where conciousness is made up of mind (manas), intelligence (buddhi) and ego (ahamkara).
Mr. Iyengar explains that just as the brain controls physical, mental and intellectual functions through the nerve cells or neurons, chakras tap the prana or cosmic energy which is within all living beings and transform it into spiritual energy.  This energy is then spread through the body by the nadis, or channels.
There are 11 chakras of which 7 are major.  These seven are the Muladhara chakra, Swadhishtana chakra, Manipuraka chakra, Anahata chakra, Vishuddhi chakra, Ajna chakra and Sahasrara chakra.  We will explore more into each of these seven chakras over the next few blogs.
The practice of yoga is to awaken the divine energy within every human and unite prakriti with purusha.  As Mr.Iyengar states, "asanas and pranayama uncoil and alert the chakras.  In the process, the nadis are activated. This causes the chakras to vibrate and to generate energy."
Since emotions are rooted in the chakras, the energy can become blocked creating physical and emotional issues.  When prana is flowing freely through the chakras we feel a sense of calmness, balance and serenity - at one with the world.

Namaste.
Pamela Nelson
www.plnyoga.vpweb.com

Above picture from:
http://www.reiki-for-holistic-health.com/chakra-aura-picture.html