In Hindu mythology and philosophy, Om is the sacred syllable used as a symbol of ultimate reality.
Om, also written Aum, is one of the most important sacred sounds in Hindu traditions. The syllable appears in the Upanishads and is used in meditation, prayer, mantra recitation, and ritual openings. It is often interpreted as representing the totality of existence and the underlying reality called Brahman.
The sound is commonly explained through its three phonetic components—A, U, and M—followed by silence. Different texts and schools connect these parts with multiple triads, including waking, dreaming, and deep sleep, or creation, preservation, and destruction. These interpretations vary, but they share the idea that Om encompasses the whole range of experience.
Om is not the same as the Gayatri, a highly revered Vedic mantra, or namaste, a respectful greeting and gesture. Aum is an alternate transliteration that reflects the syllable’s traditional pronunciation and structure.