|Longchen Rabjam composed commentaries to the major Nyingtik traditions)]
The Nyingtik (Wyl. snying thig or snying tig) teachings are the innermost secret teachings of Dzogchen.
The Dzogchen teachings were revealed to Prahevajra (Tib. Garab Dorje) by Vajrasattva, and passed down through an unbroken lineage to present day masters. Within the Dzogchen teachings, there are three categories of teachings suitable to students of different capacity. The Nyingtik is the innermost secret unsurpassed cycle of teachings (Wyl. yang gsang bla na med pa'i skor) of the Category of Pith Instructions; this cycle is the most direct approach for students of the highest capacity.
Within the Nyingtik teachings, there are tantras (Tib. gyü) and instructional (Tib. mengak) texts. Regarding the instructional texts, Tulku Thondup explains:
It is mainly based on the Longsal Barma tantra. 
In the fourteenth century in Tibet, the great master Longchen Rabjam became the lineage holder of both of these Nyingtik traditions, and wrote a commentary on each tradition (see Nyingtik Yabshyi).
Tulku Thondup continues: