The document provides background information on the Karmapa lineage of Tibetan Buddhism. It discusses how the lineage started with Dusum Khyenpa in the 12th century and has continued through 16 recognized reincarnations, with the most recent being the 17th Karmapa, Trinlay Thaye Dorje. It also explains that the Karmapas are believed to be manifestations of the bodhisattva Avalokiteshvara, working to benefit all sentient beings. The lineage has passed down the teachings of Mahamudra meditation from master to disciple over the centuries.