This article is from the Magick Tantra FAQ, by Tyagi Nagasiva nagasiva@luckymojo.com, Catherine Yronwode cat@luckymojo.com with numerous contributions by others.
Tantra yoga is a general name for a confluence of mystical
and religious systems developed in India over the past
several centuries in reflection of certain traditional
texts, called 'Tantras,' often attributed to divinities
or mythological beings.
Tantric systems maintain a variety of cosmological
presuppositions, sometimes biological in metaphor (e.g.
disks or wheels -- chakras -- of energy or 'prana' that may
be found throughout the body and in particular along the
spine), sometimes religious in character (e.g. the
disciplines which attempt to influence the deities Siva
and/or Sakti, thought to be resident to the human body).
Typically yoga is an ascetic set of disciplines recommended
by a historical or tutelary guru or instructor and is
presumed to aid the practitioner in purificatory, conscious,
or moral development.
Tantra (sometimes "tantric") yoga in particular often
includes a context of sexual symbolism, if not actual sexual
activities, which are described as constituting this aid.
Often there will also be an ultimate aim supposed (e.g.
"moksha" or "liberation") which serves to bolster the
practices based on a presumed cosmology (e.g. better
rebirths or an escape from rebirth into the world).
For a further historical description of some the varied
traditions of Indian tantra yoga, see also
http://www.hubcom.com/magee/tantra
This site provides an overview of a variety of Tantras
[texts], including many techniques and basic ideas. It
also includes a bibliography that will point you toward
more sources.
Buddhist tantra yoga developed as an offshoot from Hindu
tantra centuries ago. Some lineages of Chinese Buddhist tantra
also incorporate concepts and practices from Taoist sexual
alchemy. One contemporary teacher of Buddhist tantra yoga
is Grand Master Lu, a Taiwanese-born monk working in the
Tibetan Buddhist tradition. Some of his articles on
contemporary tantric Buddhism are archived at these URLs
Three Basic Homework Assignments for Tantric Practitioners:
http://www.luckymojo.com/esoteric/religion/buddhism/tibetan/threehomeworks.txt
Consort Practice:
http://www.luckymojo.com/esoteric/religion/buddhism/tibetan/consortpractice.txt
 
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