Vajrayàna is a form of Buddhism that evolved out of Mahayana during the 7th or 8th centuries in India. The name means ‘the Diamond Way' and refers to the supposedly unbreakable logic Vajrayànists use to support their interpretation of the Dhamma.
Vajrayàna is also sometimes called Tantrayàna, tantras being esoteric religious texts. Today Vajrayàna Buddhism is practiced in Mongolia, Tibet, Bhutan and in some areas in the Indian Himalayas. Of late Vajrayàna has become very popular in the West, due to the influence of the Dalai Lama and many Tibetan monks teaching there.