There is only one supreme, transcendent and universal being or god in Zoroastrianism and the name given to this entity is “Ahura Mazda”. The name derives itself from two different words in the Avestan Language. Ahura meaning “Being” while Mazda meaning “Mind”. According to Zoroaster, the founder of the religion – Ahura Mazda is most definitely almighty but not always omnipotent. He further keeps the two sides of the supreme being as represented by the name separate throughout the Gathas.
According to many scholars, Zoroastrianism sees both the mind and being as immanent entities. In other words, it is best described as a self-creating universe that has consciousness, which is pretty close in its origins or theory to that of Indian Brahmanism. Nevertheless, it is widely believed and agreed that the creation of Ahura Mazda follows the sequence of asha, truth and order. The exact opposite to this is the thesis of chaos that follows the order of druj, falsehood and disorder. It is because of the struggle between these two sides that the entire universe and humans have to stay in a constant state of flux, fighting a battle.
Angra Mainyu is the representation for chaos in Zoroastrian traditions. It is also called Ahriman or the Destructive Principle. The exact opposite and thus the referral to Ahura Mazda is called Spenta Mainyu or the Bounteous Principle. The fact that the latter transcends the former is why humankind exists. It is also the reason why the Creator can interact with the whole world.