The Moirai, or Fates, in Greek mythology, are three sisters: Clotho, Lachesis, and Atropos. They govern human destiny by spinning, measuring, and cutting the thread of life. Clotho spins the thread, Lachesis determines its length, and Atropos cuts it, thereby controlling the circumstances of birth and death. Their influence underscores the belief that human lives are subject to predetermined fates, highlighting themes of inevitability and the limitations of free will.