Chakra (“wheel” from Sanskrit) translates as a center or an accumulation of energy in our energetic body, which is interconnected into our physical body. Prana – the life force energy, flows through pathways in our energetic system creating those centers.
Generally, it is believed that there are seven main chakras located along our spine, though some of the ancient texts mention hundreds of other smaller chakras throughout the whole body.
The energetic state of each chakra has an effect on our physical body and its physiological functions (circulatory system, nervous system, internal organs etc.), our psychological and sensory system, as well as our emotions and feelings.
By nature energy flows freely throughout our whole body, although it can get blocked in some areas and flow irregularly, causing negative effects on our physical, psychological and emotional well being. Therefore, each illness is considered to be an abrupt (irregular) flow of energy, which has materialized itself as a sickness on a physical level. It happens due to some chakras getting more active (as more energy accumulates there) and others becoming less functional (less energy flows there). However, the energy can be manipulated in order to balance it out and bring body back into its natural healthy state again.
There are various tantric and yogic methods that work on the energy and those chakras and there is a lot to say and learn about each chakra individually, so only a brief description of them is given below.