Mandalas are a representation of the cosmic creation in a geometric form. The word literally means cosmos. Used in Tibetan Buddhism it is related to the Yantras of Hinduism.
Mandalas are used for meditation to induce stillness of the mind. The focus should be from the outer to the inner concentrating on the centre.The way to meditate is to gaze at the mandala with your eyes relaxed.
This is mandala that I painted, just to give you an idea.