Advaita Vedanta is a philosophical school of thought within Hinduism that focuses on the concept of non-dualism. The term "Advaita" means "not two" or "non-dual," and "Vedanta" refers to the end of the Vedas, the ancient Hindu scriptures. This school of thought is based on the teachings of the Upanishads, which are considered the final and most profound teachings of the Vedas.

According to Advaita Vedanta, the ultimate reality, known as Brahman, is the only true existence and everything else is an illusion. This concept is known as "Maya," and it states that the material world we perceive is not real, but rather a projection of our own minds. The true nature of reality, according to Advaita Vedanta, is beyond our limited human understanding and can only be experienced through self-realization.

At the core of Advaita Vedanta is the belief in the oneness of the self (Atman) and Brahman. The self, or individual consciousness, is believed to be the same as the ultimate reality, Brahman. This means that every individual is essentially a manifestation of the same divine consciousness, and the only thing that separates us from Brahman is our ignorance and illusion.

To achieve self-realization and understand the true nature of reality, Advaita Vedanta emphasizes the practice of self-inquiry and meditation. By questioning the nature of the self and the world around us, one can gradually overcome the illusion of duality and realize the oneness of the self and Brahman.

Advaita Vedanta also places a strong emphasis on the concept of "neti neti," which means "not this, not that." This practice involves negating all external and internal perceptions, thoughts, and concepts in order to reach a state of pure awareness and realization of the true self.

One of the key figures in the development of Advaita Vedanta was the 8th-century philosopher and teacher, Adi Shankara. He wrote commentaries on the Upanishads and other Hindu scriptures, and his teachings have had a significant impact on the development of Hindu philosophy and spirituality.

In conclusion, Advaita Vedanta is a school of thought that emphasizes the oneness of the self and Brahman, and the illusion of duality in the material world. Through self-inquiry and meditation, one can overcome ignorance and realize the ultimate truth of non-dualism.