“Om is the one eternal syllable of which all that exists is but the development. The past, the present, and the future are all included in this one sound, and all that exists beyond the three forms of time is also implied in it”.
There is harmony, peace and bliss in this simple but deeply philosophical sound. By vibrating the sacred syllable Om, the supreme combination of letters, if one thinks of the Ultimate Personality of Godhead 
and quits his body, he will certainly reach the highest state of “stateless” eternity, states the Bhagvad Gita.
and quits his body, he will certainly reach the highest state of “stateless” eternity, states the Bhagvad Gita.A stands for Creation
U stands for Preservation
M stands for Destruction or dissolution
Om provides a dualistic viewpoint. On one hand, it projects the mind beyond the immediate to what is abstract
and inexpressible. On the other hand, it makes the absolute more tangible and comprehensive. It encompasses all potentialities and possibilities; it is everything that was, is, or can yet be. It is omnipotent and likewise remains undefined.
During meditation, when we chant Om, we create within ourselves a vibration that attunes sympathy with the cosmic vibration and we start thinking universally. The momentary silence between each chant becomes palpable. Mind moves between the opposites of sound and silence until, at last, it ceases the sound. In the silence, the single thought—Om—is quenched; there is no thought. This is the state of trance, where the mind and the intellect are transcended as the individual self merges with the Infinite Self in the pious moment of realization. It is a moment when the petty worldly affairs are lost in the desire for the universal. Such is the immeasurable power of Om.
The A and U are essential to the sound as M, or as the silence (turiya) against which the sound appears. Moreover, it would be a mistake to say that AUM did not exist while the silence reigned; for it would be still potentially present even in the silence. The actual manifestation of the syllable, on the other hand, is fleeting and evanescent, whereas the silence abides. The silence, indeed, is present elsewhere during a local pronunciation of the AUM – that is to say (by analogy), transcendentally during the creation, manifestation, and dissolution of the universe.
THE WORLD (SRUSHTI) IS BASED ON “OM”. If one has started to understand ” OM “, will meet with the infinity.
IT IS BIG IMPORTANCE OF OM IN MEDITATION. ALL ETERNAL PEACE AND LIVES ARE IN AUM JUST ONE HAS TO REALIZE THE IMPORTANCE OF OM.
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