Niels Bohr made groundbreaking contributions to quantum mechanics and atomic structure. His model of the atom, which depicts electrons orbiting the nucleus at specific energy levels, was revolutionary in understanding atomic behavior. Bohr introduced the concept of quantum jumps, where an electron can transition between energy levels, thus explaining spectral lines in hydrogen. His work earned him the Nobel Prize in Physics in 1922. Bohr’s philosophy on the complementarity principle also influenced the philosophical analysis of scientific methodology and the nature of reality in quantum physics.