© zyxzevn

There are many words for chi in every culture. 

The common name for Chi in the west is "Life-energy", or even "Will-power"
Other common names are:
prana - India / Yoga
mana

There are many different types of chi. In some schools they are called "elements" or "tattvas".

What is not chi?

Chi is life-force, and something that is not living does not produce chi.
So chi is not electric, not magnetic, not gravity, no physical energy of any kind.
These physical forces may change the flow of chi, but they are not chi themselves.

2 different types
The chinese version of energy is more based on the body and distinguishes different meridians. It is based on the "Hara"-line, which is a vertical line through the body. Its source is the earth.
It is used in many fighting sports (martial arts).

The version from india is more based on the chackras. These are like vortices on different places on the body. From and to the chackras there are many streams which are called nadis. 

The main stream is called the kundalini, and its centre is the nadi-brahma. It is like the ultimate
source of prana/chi.
This model is used in yoga.

yet, there are more types

There is another system that is less published, but its chi is related to what we experience as "identity". And in some forms it can be experienced as love. It seems that some christian and some buddhist traditions use this form. (Diamond sutra)

Then there is a form which I can only describe as "harmony". It is like being in flow with everything. The traditions that are derived from it are native american, buddhism and zen.

My own opinion is that all these variations are like different aspects of the same.