Moksha is, in Hindu tradition, liberation from saṃsāra — the cycle of birth, death, and rebirth — and the simultaneous realization that the individual self (ātman) is not separate from the ultimate reality (brahman).
It is the fourth and final puruṣārtha, or aim of life, after dharma (ethical living), artha (prosperity), and kāma (pleasure). Different schools of Hindu thought disagree on what moksha is and how it is reached: Advaita Vedānta treats it as the recognition of non-duality, devotional traditions cast it as eternal communion with a personal deity, and yogic disciplines describe it as the cessation of mental fluctuation. Jain and Buddhist traditions inherit related concepts under different names and different metaphysical commitments.
What unites the versions is the structural move: liberation is not an external reward but a shift in what one understands oneself to be — the dropping of identification with the apparently bounded self, not its preservation.