Tantra explains (Tanoti) in great detail the knowledge concerning Tattva (Truth or Brahman) and Mantra (mystic syllables). It saves (Trayate). Hence it is called Tantra.
Tantra Yoga is the path of ritual and perhaps the most misunderstood path. Some may think of Tantra Yoga as sorcery, witchcraft, magic spell or some mysterious formula. Most people perceive Tantra Yoga as sexual. All of these perceptions are far from truth. Tantra is the knowledge concerning Tattva (Truth) and Mantra (mystic syllables). It utilizes rituals to respectfully experience the sacred in everything we do, not just sex though sex is a part of it. It aims to expand our awareness in all states - whether awake or asleep. Tantra Yoga practitioners must have purity, humility, devotion, courage, dedication to his Guru, cosmic love, faithfulness, contentment, dispassion, non-covetousness, and truthfulness.
Tantric yoga suggests that sexuality can be a very powerful force that can be harnessed for increased self-awareness. Thus, tantric yoga is unusual, in that it not only allows sexual feelings and contact, but uses sexual experience as a means to enlightenment. The emphasis is not on the sexual release as an end in and of itself, but rather on sex as a channel through which the evolution of self may proceed.
Tantra Yoga lays special emphasis on the development of the powers latent in the six Chakras, from Muladhara to Ajna. Kundalini Yoga actually belongs to Tantric Sadhana which gives a detailed description about this serpent-power and the Chakras (plexus). Entire Tantric Sadhana aims at awakening Kundalini, and making her to unite with Lord Shiva, in the Sahasrara Chakra. Methods adopted to achieve this end in Tantric Sadhana are Japa of the Name of the Mother, prayer, and various rituals.
Reality as Shiva-Shakti According to Tantra, Reality is pure consciousness (chit), which is considered to be identical with both being (sat) and bliss (ananda). In Tantra, this being-consciousness-bliss or Satchidananda is enshrined as Shiva~Shakti, a conjoined term conveying the inseparable nature of Shiva (the Absolute) and Shakti (the power of creation). In Tantra, any conception of the Divine which does not include Shakti, or the power to become, is considered to be incomplete.
Western views of Tantra
Sir John Woodroffe The first Western scholar to take the study of Tantra seriously was Sir John Woodroffe (1865–1936), who wrote about Tantra under the pen name Arthur Avalon. He is generally held as the "founding father of Tantric studies."Unlike previous Western scholars, Woodroffe was an apologist for Tantra, defending Tantra against its many critics and presenting Tantra as an ethical philosophical system greatly in accord with the Vedas and Vedanta. Woodroffe himself practised Tantra as he saw and understood it and, while trying to maintain his scholastic objectivity, was considered a student of Hindu Tantric (in particular Shiva-Shakta) tradition.Further development Following Sir John Woodroffe, a number of scholars began to actively investigate the Tantric teachings. These included a number of scholars of comparative religion and Indology, such as: Agehananda Bharati, Mircea Eliade, Julius Evola, Carl Jung, Giuseppe Tucci and Heinrich Zimmer. According to Hugh Urban, Zimmer, Evola and Eliade viewed Tantra as "the culmination of all Indian thought: the most radical form of spirituality and the archaic heart of aboriginal India", and regarded it as the ideal religion of the modern era. All three saw Tantra as "the most transgressive and violent path to the sacred." Zimmer praised Tantra as having a world-affirmative attitude: "In the Tantra, the manner of approach is not that of Nay but of Yea ... the world attitude is affirmative ... Man [sic] must approach through and by means of nature, not by rejection of nature".
Tantra in the modern world Following these first presentations of Tantra, other more popular authors such as Joseph Campbell helped to bring Tantra into the imagination of the peoples of the West. Tantra came to be viewed by some as a "cult of ecstasy", combining sexuality and spirituality in such a way as to act as a corrective force to Western repressive attitudes about sex. As Tantra has become more popular in the West it has undergone a major transformation, which has made Modern Tantra, or the New Age interpretations of Tantra, more properly called Neotantra, different from the original Tantric traditions of India. For many modern readers, "Tantra" has become a synonym for "spiritual sex" or "sacred sexuality", a belief that sex in itself ought to be recognized as a sacred act which is capable of elevating its participants to a more sublime spiritual plane. Though Neotantra may adopt many of the concepts and terminology of Indian Tantra, it often omits one or more of the following; the traditional reliance on guruparampara (the guidance of a guru), extensive meditative practice, and traditional rules of conduct - both moral and ritualistic.