What can Einsteins equation be used to calculate?

Einstein's equation, (E=mc^2), can be used to calculate the energy (E) equivalent of a mass (m) at rest, where (c) represents the speed of light in a vacuum (approximately (3 \times 10^8) meters per second). This relationship illustrates the principle of mass-energy equivalence, indicating that mass can be converted into energy and vice versa. It has applications in nuclear physics, such as in the calculations of energy released in nuclear reactions or the energy produced by particle-antiparticle annihilation.