Nisargadatta Maharaj was a cigarette seller in Mumbai, who later became a spiritual teacher. He met his Guru Siddharameshwar Maharaj in 1933, which led to his spiritual transformation. He emphasized self-inquiry and meditation on the feeling of "I am" to uncover the illusory nature of self.
His teachings were compiled in the book I Am That by Maurice Frydman. His teachings align with those of Ramana Maharshi (1879 - 1950), both emphasizing the illusory nature of the ego and the importance of realizing one's true nature. Ramesh Balsekar (1917 - 2009) was a retired banker and renowned Advaita Vedanta practitioner who carried on the work.