Nirvana is a key concept in Hinduism and Buddhism that represents the ultimate state of liberation from the cycle of birth, death, and rebirth (samsara). In this state, individuals experience freedom from suffering and the ego, achieving a profound realization of truth and unity with the divine essence. This concept is deeply connected to ideas like Brahman (the ultimate reality) and Atman (the individual self), as attaining nirvana signifies realizing one's true nature as identical with Brahman.