Mantra is a divine combination of divine syllables or sounds
which when chanted with devotion,faith and emotion gravitate the concerned God or Goddess or deity and secure their divine blessings. For divine help one must link with divine forces but majority of humans are unaware of these forces and have no link whatsoever. But when an individual starts chanting Mantra related to a particular deity regularly the gap between him and the concerned divine force steadily decreases. By regular use of Mantra a subtle link is formed and through this one could then obtain any desired boon within the power of the deity. One could obtain wealth, prosperity, fame, fearlessness, success and spiritual upliftment, but for each a different Mantra is chanted and a different deity propitiated.
A Mantra is a special set of words through only that particular deity could be summoned. If I write or speak in Chinese you won't be able to understand and my words will not produce any effect. But if I speak the language you know its effect shall be with doubt. Praying to these deities in one's language won't help much but if one uses the words that they can understand the result shall be instant.
A hypothesis and the principles derived out of it make the rock bottom of any systemised knowledge. When the same principle is ascertained as law, it is rendered the form of pure science. Now it is clear that science is the knowledge brought under general principles through minute analysis and experimentation.
Tantra is an eminent science having thousands of principles. In fact, it is the system of our life and a science of practice and practical knowledge. Through Tantra, we can attain superb powers by attracting and deriving the divine faculties pervading the entire cosmos. The aspirant of Tantra makes his internal capacity sharp and intensely forceful just like a magnet. This science is the process of activating the various dormant vital glands and Chakras of the astral form, present inside the human body. It makes us aware of the truth that a person can get liberation from his own subjugation, can achieve immense power and even with the physical body present, can free himself from his body and expand his faculties infinitely.
Each and every element of the nature is associated with the other. Every action has a definite basis and for that action, there also exists an equal and opposite reaction. This uninterrupted succession of atomic process is going on in our atmosphere. Formation of water vapours, rain from the clouds due to attraction between positively and negatively charged atoms, storms, tempest and earthquakes, all are interrelated to each other.Tantra is the process of intensification of our peculiar inner potentialities so that we can command this atomic arrangement which in other words is known as 'Siddhi'. The flow of energy is going on ceaselessly in the environment and when your own inner energy becomes capable of influencing the external ones, nothing will remain impossible for you and this is the science of Tantra in which the aspirant's wish is first and foremost.
Basically, Yantras are the residential places of Gods & Goddesses. Every kind of Yantra has its own kind of energy and fulfill the necessities of the ‘Sadhak’. An Individual can fulfill all his requirements only by the worship of these yantra. In other words we can say that these are the basic articles from whom one can find everything on earth.