We are connected to the outside world through our five senses which are Eyes, Ears, Tongue, Nose and Skin. For each input that we receive from our senses, there is a corresponding Chemical Reaction in our body.

It produces a fluctuation in our Mind. This in turn translates to Energy waves leaving an impact on Energy Body of the person.

The reverse is also true, any thought which comes in our Mind would prompt us to produce a Physical Action. It will also have an impact on the Energy Body.

The Physical action thus performed will again have an impact on the Mental and Energy Body of the person,. This implies accumulation of Karma never stops and the person will forever be caught in a Karmic Cycle.

Ultimately the accumulated Karma gets hardened in the three bodies. This presents an obstruction to the flow of Prana in the Bodies or Koshas .

Now, accumulated Karma in a person is not just due to Karmic Cycle. It is also due to Karma from Past Lives. The Karmas from Past Lives get transported into this life as the Soul finds a new Body.

To summarize, Karma is Memory Imprints of this life and the past lives on Quantum of Prana that flows in the body.

The Karmic Memories makes one person different from other person. It decides how Prana or the Life Energy will flow and behave in each person.

Sadhguru has explained why Prana behaves in a certain way in each person through an example of Smart Electricity in the following video.