ॐ भूर्भुवः स्वः Oṃ Bhūr-Bhuvaḥ Svaḥ
तत्सवितुर्वरेण्यं । Tat-Savitur-Varennyam |
भर्गो देवस्य धीमहि Bhargo Devasya Dhīmahi
धियो यो नः प्रचोदयात् ॥ Dhiyo Yo Nah Pracodayāt ||
1: Om, (that Divine Illumination which Pervades the) Bhu Loka (Physical Plane, Consciousness of the Physical Plane), Bhuvar Loka (Antariksha or Intermediate Space, Consciousness of the Prana) and Swar Loka (Swarga, Heaven, Consciousness of the Divine Mind),
2: On that Savitur (Divine Illumination) which is the Most Adorable (Varenyam), …
3: … and which is of the nature of Divine Effulgence (Bhargo Devasya), I meditate,
4: May that Divine Intelligence (Dhiyah) Awaken (Pracodyat) our (Spiritual Consciousness).
From Wikipedia, the free encyclopedia
The Gāyatrī, also known as the Sāvitrī mantra, is a highly revered mantra from the Rig Veda (Mandala 3.62.10), dedicated to Savitr, the sun deity. Gāyatrī is the name of the Vedic meter in which the verse is composed. Its recitation is traditionally preceded by oṃ and the formula bhūr bhuvaḥ svaḥ, known as the mahāvyāhṛti, or “great (mystical) utterance”. Vishvamitra is said to have created the Gayatri mantra.
The Gayatri mantra is cited widely in Vedic and post-Vedic texts, such as the mantra listings of the Śrauta liturgy, and classical Hindu texts such as the Bhagavad Gita, Harivamsa, and Manusmṛti. It is also praised by the Buddha in the Pali Canon. The mantra is an important part of the upanayana ceremony for young males in Hinduism and has long been recited by dvija men as part of their daily rituals. Modern Hindu reform movements spread the practice of the mantra to include women and all castes and its use is now very widespread.
The main mantra appears in the hymn RV 3.62.10. During its recitation, the hymn is preceded by oṃ (ॐ) and the formula bhūr bhuvaḥ svaḥ (भूर् भुवः स्वः). This prefixing of the mantra proper is described in the Taittiriya Aranyaka (2.11.1-8), which states that it should be chanted with the syllable oṃ, followed by the three Vyahrtis and the Gayatri verse. Whereas in principle the gāyatrī mantra specifies three pādas of eight syllables each, the text of the verse as preserved in the Samhita is one short, seven instead of eight. Metrical restoration would emend the attested tri-syllabic vareṇyaṃ with a tetra-syllabic vareṇiyaṃ.
The Gayatri mantra is, in Devanagari:
ॐ भूर्भुवः स्वः ।
भर्गो॑ दे॒वस्य॑धीमहि ।
धियो॒ यो नः॑ प्रचो॒दया॑त् ॥
oṃ bhūr bhuvaḥ svaḥ
dhiyo yo naḥ pracodayāt
– Rigveda 3.62.10
See also: Surya
The Gāyatrī is dedicated to Savitr, a Vedic Sun deity.
The Gayatri mantra has been translated in many ways.[note 1] Quite literal translations include:
Monier Monier-Williams(1882): “Let us meditate on that excellent glory of the divine vivifying Sun, May he enlighten our understandings.”
Ralph T.H. Griffith (1896): “May we attain that excellent glory of Savitar the god: So may he stimulate our prayers.”
More interpretative translations include:
Shriram Sharma : Om , the Brahm , the Universal Divine Energy , vital spiritual energy (Pran), the essence of our life existence, Positivity , destroyer of sufferings , the happiness , that is bright, luminous like the Sun , best, destroyer of evil thoughts , the divinity who grants happiness may imbibe its Divinity and Brilliance within us which may purify us and guide our righteous wisdom on the right path. 
Sir William Jones (1807): “Let us adore the supremacy of that divine sun, the god-head who illuminates all, who recreates all, from whom all proceed, to whom all must return, whom we invoke to direct our understandings aright in our progress toward his holy seat.”
William Quan Judge (1893): “Unveil, O Thou who givest sustenance to the Universe, from whom all proceed, to whom all must return, that face of the True Sun now hidden by a vase of golden light, that we may see the truth and do our whole duty on our journey to thy sacred seat.”
Sivanath Sastri (Brahmo Samaj) (1911): “We meditate on the worshipable power and glory of Him who has created the earth, the nether world and the heavens (i.e. the universe), and who directs our understanding.”[note 2]
Swami Vivekananda: “We meditate on the glory of that Being who has produced this universe; may He enlighten our minds.”
(1947): “We meditate on the effulgent glory of the divine Light; may he inspire our understanding.”
(1953): “We meditate on the adorable glory of the radiant sun; may he inspire our intelligence.”
Swami Sivananada: “Let us meditate on Isvara and His Glory who has created the Universe, who is fit to be worshipped, who is the remover of all sins and ignorance. May he enlighten our intellect.” ( Om – Para Brahman; Bhur – Bhuloka (Physical Plane); Bhuvah – Antariksha Svah; Svarga Loka Tat – Paramatma Savitur; Isvara (Surya); Varenyam; Fit to be worshipped; Bhargo – Remover of sins and ignorance; Devasya – Glory (Jnana Svaroopa); Dheemahi – We meditate; Dhiyo – Buddhi (Intellect); Yo – Which; Nah – Our; Prachodayat – Enlighten )
Vedic and Vedantic literature
The Gayatri mantra is cited widely in Vedic and post-Vedic texts, such as the mantra listings of the Śrauta liturgy,[note 3][note 4] and cited several times in the Brahmanas and the Srauta-sutras.[note 5][note 6] It is also cited in a number of grhyasutras, mostly in connection with the upanayana ceremony in which it has a significant role.
The Gayatri mantra is the subject of esoteric treatment and explanation in some major Upanishads, including Mukhya Upanishads such as the Brihadaranyaka Upanishad,[note 7] the Shvetashvatara Upanishad[note 8] and the Maitrayaniya Upanishad;[note 9] as well as other well-known works such as the Jaiminiya Upanishad Brahmana.[note 10] The text also appears in minor Upanishads, such as the Surya Upanishad.
The Gayatri mantra is the apparent inspiration for derivative “gāyatrī” stanzas dedicated to other deities. Those derivations are patterned on the formula vidmahe – dhīmahi – pracodayāt”, and have been interpolated into some recensions of the Shatarudriya litany.[note 11] Gāyatrīs of this form are also found in the Mahanarayana Upanishad.[note 12]
The Gayatri mantra is also repeated and cited widely in classical Hindu texts such as the Bhagavad Gita, Harivamsa, and Manusmṛti. 
In Samyutta Nikaya 111, Majjhima Nikaya 92 and Vinaya i 246 of the Pali Canon, the Buddha refers to the Agnihotra as the foremost sacrifice and the Gayatri mantra as the foremost meter:
aggihuttamukhā yaññā sāvittī chandaso mukham.
Sacrifices have the agnihotra as foremost; of meter the foremost is the Sāvitrī.
Imparting the Gayatri mantra to young Sanatan men is an important part of the traditional upanayana ceremony, which marks the beginning of study of the Vedas. Sarvepalli Radhakrishnan described this as the essence of the ceremony, which is sometimes called “Gayatri diksha”, i.e. initiation into the Gayatri mantra. However, traditionally, the stanza RV.3.62.10 is imparted only to Brahmin boys. Other Gayatri verses are used in the upanayana ceremony for non-Brahmins: RV.1.35.2, in the tristubh meter, for a kshatriya and either RV.1.35.9 or RV.4.40.5 in the jagati meter for a Vaishya.
Gayatri japa is used as a method of prāyaścitta, instrument of Tantric practice. It is believed by practitioners that reciting the mantra bestows wisdom and enlightenment, through the vehicle of the Sun (Savitr), who represents the source and inspiration of the universe.
In 1827 Ram Mohan Roy published a dissertation on the Gayatri mantra that analysed it in the context of various Upanishads. Roy prescribed a Brahmin to always pronounce om at the beginning and end of the Gayatri mantra. From 1830, the Gayatri mantra was used for private devotion of Brahmos. In 1843, the First Covenant of Brahmo Samaj required Gayatri mantra for Divine Worship. From 1848-1850 with the rejection of Vedas, the Adi Dharma Brahmins use the Gayatri mantra in their private devotions.
In the later 19th century, Hindu reform movements spread the chanting of the Gayatri mantra. In 1898 for example, Swami Vivekananda claimed that, according to the Vedas and the Bhagavad Gita, a person became a Brahmin through learning from his Guru, and not because of birth. He administered the sacred thread ceremony and the Gayatri mantra to non-Brahmins in Ramakrishna Mission. This Hindu mantra has been popularized to the masses, outside of Brahminic culture through pendants, audio recordings and mock scrolls. Various Gayatri yajñas organised by All World Gayatri Pariwar at small and large scales in the late twentieth century also helped spread the Gayatri mantra to the masses.
A version of the Gayatri mantra is featured in the opening theme song of the TV series Battlestar Galactica (2004). A variation on the William Quan Judge translation is also used as the introduction to Kate Bush’s song “Lily” on her 1993 album, The Red Shoes. In her Living Proof: The Farewell Tour, the singer/actress Cher sang the Gayatri mantra while riding a mechanical elephant. She later reprised the performance during her Classic Cher tour. The Swiss avantgarde black metal band Schammasch adapted the mantra as the outro in their song “The Empyrean” on their last album “Triangle” as a Gregorian chant.