Ik Onkar (also ੴ, ਇੱਕ ਓਅੰਕਾਰ, Ikk Oankar) is a central tenet of Sikh religious philosophy.[1] It is a symbol of the unity of God in Sikhism, and is found on all religious scriptures and places such as Gurdwaras.
Derived from Sanskrit, Ik Onkār is the first phrase in the Mul Mantra referring to the existence of "one God;"[2] It is found in the Gurmukhi script[3] and is consequently also part of the Sikh morning prayer, Japji Sahib. It is a combination of two characters: the numeral Ik (one) and the first letter of the word Onkar (God) - which also happens to be the first letter of the Gurmukhī script, with a specially adapted vowel symbol.

In Mul Mantra



Illuminated Adi Granth folio with nisan (Mul Mantra) of Guru Gobind Singh, showing Ik Onkār. Collection of Takht Sri Harimandir Sahib, Patna.
It was also the opening phrase of the Mul Mantra, present as opening phrase in the Guru Granth Sahib, and the first composition of Guru Nanak. Further, the Mul Mantra is also at the beginning of the Japji Sahib, followed by 38 hymns and a final Salok at the end of this composition.
Simplified transliteration: ik ōnkār satināmu karatā puraku nirabhǎ'u niravèr akāl mūrat ajūnī sèbhang guraprasād ||
English: One Universal Creator, the Name is Truth, Creative Being (personified), Without fear, Without hatred, timeless Image, beyond birth, Self-existent, by the Guru's Grace.

The phrase's monotheistic quality is further clarified by Guru Nanak in his composition (Guru Nanak, Guru Granth Sahib, 929).:
onkār brahamā utapata
"From Onkār, the Creator Brahma was created."
[citation needed]
Stating that God, creating Brahma, predated that being.