Aadi guru Shankaracharya was the Reviver of Hindu dharma and the father of Advaita philosophy. At the tender age of 4, Adi Guru Shankaracharya Ji started reciting the complex hymns from the Vedas. As per Shaiv's philosophy, Bhagwan Vishnu instructed lord Shiva to incarnate in the Kaliyuga. The form lord Shiva took was of Adi Shankara who was the re-establisher of Sanatan dharma by establishing the faith back on Vedic Scriptures.
Aadi guru Shankaracharya was the pioneer of The Advaita school of thought. This school of Hindu philosophy believes in the concept of non-duality. As per advaitism, there is an absence of separation between the subject (Bramh) and the subject (aatma). advaitism is based on Upanishad philosophy which advocates that there is no difference between the soul and absolute reality, god. Based on this philosophy, Aadi Guru Shankaracharya revived the roots of corrupted Sanatan dharma. The great Guru and
Adi Shankara established four maths or monasteries in the four directions of India, along with the Char Dham, Gangotri, Yamunotri, Badrinath, and Kedarnath which are within the boundaries of Kedarkhand (Now Uttarakhand) to be held by successor disciples, who are also known as Shankaracharyas.