Celtic, Ancient Greek and Roman and Islamic traditions also used Mandala like images for religious and contemplative practices.
The meaning of Mandala in Hindu is concentric energy circle. In Mandalas there are many layers that spiral through and link consciousness with healing, sacred geometry and psychology.
Carl Jung painted Mandalas and believed that they were a representation of the “unconscious self” which then enabled the healing of emotional disorder within him. Tibetan monks and Navajo Indians are both famous for their sand Mandalas, which once completed are brushed away, symbolizing the impermanence of the material. A Buddhist Mandala will incorporate 5 elements and 5 colours. Other references within the Mandala will be to the Lotus and the 4 Noble Truths and the Eightfold path. As you can see, it becomes quite complex.
There a numerous sites on the web to access Mandalas and an interesting exercise is to take one design and have several people colour it. They will all be quite different in look and energy.