'Gayatri Mantra' is written in Rigveda. It is an ancient Indian collection of Vedic Sanskrit hymns. It is one of the four canonical sacred texts (sruti) of Hinduism known as the Vedas. The text is a collection of 1,028 hymns and 10,600 verses, organized into ten books (Mandalas). The Gayatri Mantra, also known as the Savitri mantra, is a highly revered mantra from the Rigveda (Mandala 3.62.10), dedicated to Savitr, the Sun deity. Its recitation is traditionally preceded by om and the formula bhur bhuvah svah, known as the mahavyahṛti, or "great (mystical) utterance".