Degenerate matter is a highly dense state of matter that occurs under extreme conditions, such as in the cores of white dwarfs and neutron stars. In this state, the particles are packed closely together, and quantum mechanical effects become significant. The pressure in degenerate matter arises not from thermal energy, but from the principles of quantum mechanics, particularly the Pauli exclusion principle, which prevents identical fermions from occupying the same quantum state. There are two main types of degenerate matter: electron-degenerate matter and neutron-degenerate matter. Electron-degenerate matter is found in white dwarfs, where electrons provide the pressure to counteract gravitational collapse. Neutron-degenerate matter, found in neutron stars, consists mainly of neutrons and is even denser, with neutrons providing the necessary pressure to support the star against gravity.