This Sikh symbol is actually the first text that appears in the Sri Gur Granth Sahib (the holy scripture of the Sikhs). Its meaning, "God is One" represents the universiality of the one creator across all faiths and beliefs.

The numeral "1" which is represented as "1" and pronounced ik commences the mulmantra, the root postulation of the Sikh worldview. In simple terms this part of the revelation avers that the Divine is one and without duality.

The letter E in the Sikh script, Gurmukhi, is pronounced Ong and signifies the first intimations of the Divinity to the human mind.

The remaining crescendic semi-finished oval curve so as to indicate an ellipsis is pronounced akar, which literally means, the form. For good reasons, which distinguish the Sikh Metaphysics from some others, the term akar, is always used as conjoined with the term E (Ong). Obviously, because, the phenomenal world of forms is a continuous process of inflection of Ong, the ellipsis is incomplete till the curve returns back to its starting point. This view of creation and dissolution finds mention in a revelation called Sukhmani which is recorded in Guru Granth Sahib, the Sikh scripture.

In summary of the three concepts discussed above, the first representation is the numeral source of the Cosmic whole, the second, the phenomenal appearances, and third, the activity on the material plane. The first is humanly incomprehensible, and is knowable solely by self-realization. The second is the object of Pure Consciousness, and the third, of finite mind, as informed by sense impressions. The Sikh formula, ik ongkar which is repeated over almost every chapter, division, subdivision of the Sikh Scripture, is meant to refer to the Ultimate Reality, as an indivisible Unity.

In Sikh thought, the final duality between the matter and the spirit is denied; the basic Sikh thought is strictly monistic. "From one the many emanate and finally into the one the many submerge." All that exists, whether in the form of phenomena, appearances, or as numenon and reality, is, in ultimate comprehension, the Spirit and the mind. The individual mind, the numerous forms of life, and the inanimate matter are all Spirit in different modes. Out of its own impulse and initiative of the Spirit, a process of involutions occurred for some limited purpose, the precise nature of which is beyond human comprehension. All we can say is such is its nature and such its pleasure.

Belief in one absolute and ineffable Divine reality which is beyond space and time has given the Sikhs a unique worldview derived from an ecumenical revelation that is unequivocally unique from other world religions and traditions known to humankind.

If it is sayable, it is within the range of the word.
If it is unsayable, it is outside the steady grasp of mind.
The real is where the sayable and unsayable meet.
What the real truly is, is altogether beyond comprehension

--Sri Guru Granth Sahib, page 340
ikkas te hoio annta, Nanak ikkas mahi samae jio. Sri Guru Granth Sahib, page 131