Chakras are defined as an energy vortex located in specific areas of the body. Although there are many all around the body, most of the Yoga books discuss seven main ones because they combine the Solar Plexus, the Chakra where we store our emotions, with the Navel Chakra, or the Heart Chakra.
The aim of Yoga is to awaken the kundalini energy through the spine. The energy vortex, or the Chakras, is located along the spine. All are of equal importance and work as a whole. As we open one, the rest are affected too.
We want to achieve an active and open spine, as well as a healthy nervous and glandular system, so we can put all of the Chakras to work for us. Through the practice of Yoga and Meditation, the Chakras become activated and open.
The lower Chakras represent the more mundane planes of existence, such as needs, desires, instincts, the material world, and the self. They have a lower frequency than the upper Chakras, but that doesn�t decrease their value.
One of the modern ideas that differs from the traditional yogi scriptures is the acceptance of the human body. This basically means to honor, take care, and connect with our needs, emotions, sexuality, and instinctual self.
The lower Chakras connect us with the physical world, our instincts, our emotions, and tunes into them. Vibrating them can be a source of fulfillment and satisfaction in all of the above.
The lesson is to accept everything as it is, neither good, nor bad, just what it is. This will help us to observe, without judgment, and to reach higher states of consciousness. For example, the color green is green and it is no better than or worse than the color red or any of the other colors. A rose is a rose and it is no better or worse than any other flower. A meditative state of mind can give us the gift of seeing things as they are.
The upper Chakras are associated with enlightenment, the spirit, and the knowledge of the inner self. The vibration is higher. It allows the connection with us and the others at a higher level, with universal consciousness. There is no separation.