Among all those Thankas Mandala is the most famous one. Mandala are graphic, geometric representations of the cosmos ~ Paychocos mograms symbolizing the order or harmony achieved by truly enlightened mind. They have great power, being seen as concentrated areas where the forces of the universe are gathered. (MANDA means essence while LA means container). 

The design is symmetrical, based or circles or squares, with central focal point. In tantric Buddhism where the mandala is used to support meditation, adept seek to absorb its power. Sometimes a Mandala takes the form of an elaborate four gated city '' A palace of knowledge'' which the practitioner mentally enters and approaches the centre of life in order to achieve a state of mystical unity with the Buddha. 

Although not created premanly to please the eye. Mandalas are often works art with great stylistic elegance or beauty. They are most frequently displayed on Thankas but are also seen on the walls of temples and monasteries. A few monasteries such as Shakya and Tashilhunpo still create magnificient mandalas made of colored sand.