What is the significance of mechanisms (tantra) and spells (mantra) in our lives?

Tantra and mantras are both common practices of spiritual healing and liberating the mind. In Tantra, the practitioner uses a combination of prayer, "surya" (life-force energy) visualization, yoga postures, and breathing techniques to generate blissful awareness. Guru Deities are typically portrayed with multiple arms, legs, heads (or heads with many arms), etc., demonstrating myriad different tantric yogic positions. Mantras can begin as simple words which produce a powerful effect through repetition of sound waves in the head: Om Namah Shivaya is an example that contains no letters or sounds that exist in any language known to humans.

Just as the Hindu religion give importance to astrology, in the same way, the combination of the three elements of the Tantra, Mantra and Yantra are important for worship in Hindu religion. Lets first discuss what exactly are mechanisms (tantra) and spells (mantra) .