Mantras are energy-based sounds. It produces vibration in the body. The words uttered in mantra are meaningful and are associated with the effect of vibration. This is one level of energy basis for words.
Another level is aim. Actual physical vibration when joined with a mental aim, the vibration then contains an additional component, which influences the result of saying it. Although there is a general meaning, which comes to be associated with mantras, the only lasting definition is the result or effect of saying the mantra. A Mantra can consist of a powerful word or a combination of words and can be used for self realization, for freedom from worries, to fulfill one's desires, to ward off the effects of malefic planets, to bring you success, peace and contentment -- the range is truly vast. Mantras must be chanted or recited with devotion and motivation. Chanting them as a matter-of-course deprives them of power and is practically useless from the point of view of conscious growth, evolution and effect.
Sage Vishwamitra discovered the Gayatri Mantra. This mantra enabled the sage to use rare weapons, which bowed to his will, when this mantra was invoked with faith. Through the power he attained, this way he was able to create a counterpart of the cosmos. The Gayatri Mantra is addressed to the energy of the Sun - Surya. Gayatri is the Mother of the Vedas and Gayatri Gayatri has three names - Gayatri, Saavitri and Saraswathi. Gayatri is the master of the senses, Saavitri is the master of Prana (Life Force). Saavitri signifies Truth. Saraswathi is the Presiding Deity of Speech (Vaak). Theses three represent purity of Thought, Word and Deed. The Gayatri Mantra is the universal prayer upheld in the Vedas, the most ancient Scriptures of Man. A Universal prayer is that which is to be chanted with devotion for one's spiritual benefit in all the ages in any part of the world. We have to recite the Mantra as follows.