About Three Jewels and Three Roots

In Buddhism, the Three Jewels, Triple Gem, or Three Refuges are the supports in which a Buddhist takes refuge by means of a prayer or recitation at the beginning of the day or of a practice session.
A leaf from a Prajñāpāramitā (Perfection of Wisdom) manuscript.

Tibetan Buddhist practices – Schools, sutras & tantras

Apart from classical Mahāyāna Buddhist practices like the six perfections, Tibetan Buddhism also includes tantric practices, such as and the as well as methods which are seen as transcending tantra, like . In Tibetan Buddhism, practices are generally classified as either Sutra (or Pāramitāyāna) or Tantra ( or Mantrayāna), though exactly what constitutes each category and what is included and excluded in each is a matter of debate and .
An 18th century Mongolian miniature which depicts a monk generating a tantric visualization.

Vajrayana practices – The tantric samaya vows

along with Mantrayāna, Guhyamantrayāna, Tantrayāna, Secret Mantra, Tantric Buddhism, and Esoteric Buddhism are names referring to Buddhist traditions associated with Tantra and "Secret Mantra". Practitioners of Vajrayāna need to abide by various tantric vows or pledges called samaya. These are extensions of the rules of the Prātimokṣa and Bodhisattva vows for the lower levels of tantra, and are taken during initiations into the empowerment for a particular Unsurpassed Yoga Tantra. The special tantric vows .
Samantabhadra, surrounded by numerous peaceful and fierce deities.

Tibetan Buddhist philosophical concepts you must know

In Tibetan Buddhist scholasticism, Buddhist philosophy is traditionally propounded according to a hierarchical classification of four classical Indian philosophical schools, known as the "four tenets" (drubta shyi). While the classical tenets-system is limited to four tenets (Vaibhāṣika, Sautrāntika, Yogācāra, and Madhyamaka), there are further sub-classifications within these different tenets. This classification does not include Theravada, the only surviving of the 18 classical schools of Buddhism. It also does not include other Indian Buddhist schools, such as .