The most amazing and outstanding of the Nyingma tradition is terma. Although other traditions have terma as well, and many masters of those tradition are tertons, the source of terma is Guru Rinpoche. Guru Rinpoche’s time was in the Old Translation period, when only Nyingma tradition was existent, thus most of terma texts are in the sphere of the Nyingma tradition.

~Depicted from LUMINOUS WISDOM BOOK SERIES