This scene of the yellow hat is the Gelug or Gelug-pa, also known as the Yellow Hat sect, is a school of Buddhism founded by Tsongkhapa (1357–1419), a philosopher and Tibetan religious leader. The first monastery he established was at Ganden, and to this day the Ganden Tripa is the nominal head of the school, though its most influential figure is the Dalai Lama.
A great admirer of the Kadampa (Bka'-gdams-pa) teachings, Tsongkhapa was an enthusiastic promoter of the Kadam School's emphasis on the mahāyāna principle of universal compassion as the fundamental spiritual orientation. He combined this with a strong emphasis on the cultivation of in-depth insight into the doctrine of emptiness as propounded by the Indian masters Nāgārjuna (2nd century) and Candrakīrti (7th century). Tsongkhapa said that these two aspects of the spiritual path, compassion and insight into wisdom, must be rooted in a wholehearted wish for liberation impelled by a genuine sense of renunciation. He called these the "Three Principal Aspects of the Path".