Niels Bohr was a Danish physicist born on October 7, 1885, known for his foundational contributions to atomic structure and quantum theory. He developed the Bohr model of the atom, which proposed that electrons orbit the nucleus in specific energy levels. This model helped explain how atoms emit and absorb energy. Bohr received the Nobel Prize in Physics in 1922 for his work on the structure of atoms and radiation. He also played a significant role in the development of quantum mechanics and was involved in the early stages of nuclear physics, influencing many future scientists in the field.