Qi not only forms the basis for the traditional medical systems of the East, but it has also influenced many parts of Eastern thought from martial arts to interior design.
But whatever term you use for the concept, you are referring to the energetic principle that is part of all living things.
The concept is so widespread that it has developed different terms across different languages. In Japan it is called ki.
In Vietnam, it is called khi, and in Korea it is known as Qi.
In the medical systems, it is held that the human body has natural patterns of Qi that move in certain ways and in certain patterns.
Traditional medicine seeks to restore these imbalances and deficiencies by various means, such as acupuncture, herbal preparations, and other less widely known methodologies like traditional massage and traditional exercise.
Different symptoms of each illness are said to be the result of disrupted or blocked movement of Qi across the body, or from a deficiency or imbalance of the Qi in the body.
Western medicine has been, as of yet, been unable to quantify Qi, linking its effects to everything from a placebo effect to a release of endorphins.
What western physicians have grudgingly admitted is that there is a noticeable, quantifiable effect that when added up falls under the Eastern term of Qi.