One of the key aspects of Advaita Vedanta is the awareness of the illusory nature of the material world. According to this teaching, everything in this world, including our personality and environment, is an illusion, Maya. This illusion arises from our ignorance and attachment to material things and is an obstacle to the realization of our true nature.
To distinguish illusion from reality, Advaita Vedanta suggests using three methods of cognition: Pramana (the source of knowledge), Prapancha (the material world) and Correct Understanding. Proper understanding is the key to realising the true nature, and it is achieved through the study of sacred texts and the practice of meditation.
When a person realizes his true nature as Atman and distinguishes illusion from reality, this leads to liberation from suffering and attachments.