Tantra defined -- perhaps the most popular and yet most misunderstood of yogic teachings today, is a vast ocean of ancient wisdom for enlightening the mind and the body.
Tantra -- the sacred weaving
The word Tantra stems from Sanskrit roots which literally translates as web or warp (as in weaving) - within each individual - the conscious-unconscious, male-female, in breath - outbreath .
If either of these cross threads did not exist, you would only have one thread, but not the cloth. But both threads can exist without the cloth.
The cloth only exists when the threads are interwoven .. the weft and the weave.
Tantra means 'union'
This union is known by many different names .. all of which mean exactly the same thing.
Some may call it 'Yoga', some may call it 'non duality' some may call it 'Tantra' and yet others call it "Being in the mind of 'god'". I've also heard 'descent into the Void' .. 'immersion' .. and yet there are some misguided people who call this "surrender"
tantric practice
Tantra is NOT something that you do or practice. Tantra is something that does you.
Tantra is the collapse of the Cartesian, thinking, linear mind into what can best be described as 'mind-less-ness' .. a space of no-mind where you do not control, think, focus or concentrate but can be aware that experiences move through you ... to a point where there is a total merging of you, the personality which has the experience, with both the experience and the act of experiencing.
Tantric Yoga
Tantrica, Tantra or Sacred Tantric Practice, in its purest form, describes both the process and methodologies for the resolution of all conflicts of opposites.
From earliest times, the symbology used has been based on the interpenetration of what is, metaphorically, referred to as male - female. In modern terms, it is the search for non-duality.
The metaphor covers the concept (in evolution) of the homeostasis of Ishtar-Tamuz (Babylonian), Prajna-Vajra (Buddhist), Sophia-Christos (Christianity), Isis-Osiris (Egyptian), Shekinah-Ruach (Kaballistic).
The origins of Sacred Tantric practice and doctrine can be traced back at least to the "Indus Valley" civilization that was contemporary with the Sumerian and the beginnings of the Egyptian Old kingdom. The records and doctrines and practices found in archaeological digs finds parallels in ancient Hittite worship.
popular tantra
Tantra, as currently and popularly defined and interpreted within the concept of sacred sexual practices can be considered as a defilement of the essence of Tantra. There are quite a few "New Age" self-styled "guru's" who have read some books (translated by some other self-styled guru) .. and so it goes on. This is a common occurrence within all Spirituality and Religion, (which may or may not be deliberate)
sexual tantra
Sexual Tantra is a corruption of the pure practice of Tantra as a metamorphosis of conjugates. The practice of Sexual Tantra as an approach to Yoga can have the opposite effect to pure Tantra, because the expression of the Life-force seeks Union (Yoga) with a separate partner rather than the Union of The Male and Female Essences within the individual.