In Aldous Huxley's 'Brave New World', the highest human caste is called the Alphas. They are the World State's intellectual and administrative elite, bred and conditioned for leadership, technical work, and other complex responsibilities.
The caste system descends through Betas, Gammas, Deltas, and Epsilons. Embryos are engineered in hatcheries and chemically treated before birth so that each group will fit its assigned social role. Conditioning then teaches citizens to enjoy their own caste and regard the others as inferior or undesirable.
Alphas are not simply wealthy people; social rank is built into biology, education, and psychological conditioning. Bernard Marx and Helmholtz Watson are both Alpha-Plus characters, yet each feels constrained by the society that produced him. Their dissatisfaction shows that even the highest caste lacks genuine freedom.
A common mix-up is assuming that Betas are the top class because they are also privileged. In the novel's hierarchy, however, Alpha is the highest caste, while Epsilon is the lowest. The caste names deliberately echo the Greek alphabet, reinforcing the idea of a carefully ordered social system.