Om, and why it is everywhere

Om (also written Aum) opens mantras, prayers, and scriptures. The Mandukya Upanishad begins: "Om, this syllable is all this" (verse 1), and reads its three sounds, a, u and m, as waking, dreaming, and deep sleep, with the silence after them as a fourth state: the self beyond all three. The Taittiriya Upanishad says, "Om is Brahman" (1.8).

You will see it as ॐ on doorways and in temples, and hear it at the head of every chant. Saying it slowly is itself a meditation: the sound rises from the belly (a), fills the chest (u), closes at the lips (m), then a pause. Dharamkira has a guided version.

Om is not the only sacred sound. "Om Tat Sat" seals an offering as complete (Gita 17.23). "Shanti" means peace; said three times it ends many prayers, once each for the three kinds of trouble: from ourselves, from others, from nature. "Namah" means "I bow", so many mantras end with it.

You do not need to understand every syllable to begin. You do need to say them with respect.