Om Namah Shivaya

Aum Namah Shivaya (Sanskrit Aum Namaḥ Śivāya ॐ नमः शिवाय) is a popular mantra in Hinduism and particularly in Shaivism. Its translation is "adoration (namas) to Śiva", preceded by the mystical syllable "Aum".
It is also called Panchakshara, the "five-syllable" mantra (viz., excluding the Aum). It is part of the Shri Rudram Chamakam, a Hindu prayer taken from the Black Yajurveda, and thus predates the use of Shiva as a proper name, in the original context being an address to Rudra (the later Shiva), where śiva retains its original meaning as an adjective meaning "auspicious, benign, friendly", a euphemistic epithet of Rudra.