Third Eye Meditation is meditation by concentrating at the spot betwen your eyes. Third Eye Meditation is also known as Jangama dhyana.
This is the position where the soul is located according to hinduism. This is also the spot where the Ajna Chakra is located.
You should not directly start Third Eye Meditation. You need to first start with smiple forms of meditation like concentrating your breath or mentally chanting a mantra Like OM for some time till you are able to concentrate your mind on a fixed thing without letting it drift.
Once you are confident with it you can move on to other powerfull forms of meditation.
Yes third eye meditation may have some side affects like you will have a squezing affect at the centre of the forehead and this will happen even when you are not meditating. Third eye meditation is a way for selfrealization. On this path you may attain some powers but they are to be discouraged if you wish to attain the ultimate goal of self realization.
In simple terms selfrealization simply means being aware of the cosmos and all the knowledge there is.
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