A yantra is not a diagram. The distinction matters. A diagram represents something — it is a visual aid, a schematic, a substitute for the thing it depicts. A yantra, in the tantric understanding, is a form in which the deity is actually present — a geometric structure that has been constructed through ritual, charged through mantra, and established as a living seat of the consciousness it represents. The Śrī Yantra, the nine-interlocking-triangle structure that embodies the cosmological union of Śiva and Śakti in the Śrī Vidyā tradition, is not a symbol of the Goddess Lalitā Tripurasundarī. It is, for the practitioner who has been initiated into its use, an actual presence. This study covers the major yantra forms across…