This article is from the Magick Tantra FAQ, by Tyagi Nagasiva email@example.com, Catherine Yronwode firstname.lastname@example.org with numerous contributions by others.
Tantra yoga is not alone among the various types of Indian
religion in its use of mantras (chants) and yantras
(symbolic images) to aid meditation or self-realization,
nor are such aids found exclusively in Asian religions.
Repetitious prayer and the focus of vision upon sacred
images is a world-wide phenomenon, and it is not restricted
to religions in which there is a sexual component. All
that aside, the characteristic mantras to deities such as
Siva and Kali are considered highly useful to the tantric
devotees of those entities, as are such symbolic images
and representations as the downward pointing triangle and
numerous elaborate variations of interlocked triangles.
For the non-Hindu practitioner of a sex-based mystical
system, other prayers and symbols may be of greater use;
the disciples of Austin Osman Spare, for example, focus on
a form of self-encrypted writing called sigilization
during sex-magical rites.