Ohm, Om, or Aum 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.
This symbol (as seen in the image on the right) is a sacred syllable representing Brahman, the impersonal Absolute of Hinduism — omnipotent, omnipresent, and the source of all manifest existence. Brahman, in itself, is incomprehensible; so a symbol becomes mandatory to help us realize the Unknowable. Om, therefore, represents both the unmanifest (nirguna) and manifest (saguna) aspects of God. That is why it is called pranava, to mean that it pervades life and runs through our prana or breath.
The Power of Ohm
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.
Source: About.com
