A thangka is a three-dimensional work. The picture is painted on a panel and then a silk cover is added. Sometimes it is even more embellished with leather covers on the corners and three-dimensional wooden dowels according to Buddha Net.
Thangkas are traditionally displayed at Buddhist monasteries, used in processions or hung in reverence at family alters.
The style of thangka art originated in Nepal and then imported to Tibet when a Nepali princess married a Tibetan noble according to Pink Lotus Thangka.
Thangka art usually depicts a Buddha teaching a lesson or an important scene from a Lama's life. Thangkas are used as centerpieces for mediation.
Thangka art is no longer relegated just to Tibet. People who want to learn how to make thangkas can attend schools to learn the craft. You can also buy thangkas over the Internet.