Adi Shankaracharya was an early 8th century Indian philosopher and theologian who consolidated the doctrine of Advaita Vedanta. He is credited with unifying and establishing the main currents of thought in Hinduism. His works in Sanskrit discuss the unity of the Ātman and Nirguna Brahman "brahman without attributes".

Shankara was born in the southern Indian state of Kerala, according to the oldest biographies, in a village named Kaladi sometimes spelled as Kalati or Karati. He was born to Nambudiri Brahmin parents. His parents were an aged, childless, couple who led a devout life of service to the poor. They named their child Shankara, meaning "giver of prosperity". His father died while Shankara was very young. Shankara's upanayanam, the initiation into student-life, had to be delayed due to the death of his father, and was then performed by his mother.

Shankara's hagiography describe him as someone who was attracted to the life of Sannyasa (hermit) from early childhood. His mother disapproved. A story, found in all hagiographies, describe Shankara at age eight going to a river with his mother, Sivataraka, to bathe, and where he is caught by a crocodile. Shankara called out to his mother to give him permission to become a Sannyasin or else the crocodile will kill him. The mother agrees, Shankara is freed and leaves his home for education. He reaches a Saivite sanctuary along a river in a north-central state of India, and becomes the disciple of a teacher named Govinda Bhagavatpada. The stories in various hagiographies diverge in details about the first meeting between Shankara and his Guru, where they met, as well as what happened later. Several texts suggest Shankara schooling with Govindapada happened along the river Narmada in Omkareshwar, a few place it along river Ganges in Kashi (Varanasi) as well as Badari (Badrinath in the Himalayas).

While the details and chronology vary, most biographies mention that Shankara traveled widely within India, Gujarat to Bengal, and participating in public philosophical debates with different orthodox schools of Hindu philosophy, as well as heterodox traditions such as Buddhists, Jains, Arhatas, Saugatas, and Carvakas. During his tours, he is credited with starting several Matha (monasteries), however this is uncertain. Ten monastic orders in different parts of India are generally attributed to Shankara's travel-inspired Sannyasin schools, each with Advaita notions, of which four have continued in his tradition: Bharati (Sringeri), Sarasvati (Kanchi), Tirtha and Asramin (Dvaraka). Other monasteries that record Shankara's visit include Giri, Puri, Vana, Aranya, Parvata and Sagara – all names traceable to Ashrama system in Hinduism and Vedic literature.
Shankara had a number of disciple scholars during his travels, including Padmapada (also called Sanandana, associated with the text Atma-bodha), Sureshvara, Tothaka, Citsukha, Prthividhara, Cidvilasayati, Bodhendra, Brahmendra, Sadananda and others, who authored their own literature on Shankara and Advaita Vedanta.

Adi Sankara is believed to have died aged 32, at Kedarnath in the northern Indian state of Uttarakhand, a Hindu pilgrimage site in the Himalayas. Texts say that he was last seen by his disciples behind the Kedarnath temple, walking in the Himalayas until he was not traced. Some texts locate his death in alternate locations such as Kanchipuram (Tamil Nadu) and somewhere in the state of Kerala.