Henri Becquerel was a French physicist best known for his discovery of radioactivity in 1896. His groundbreaking work laid the foundation for future research in nuclear physics and earned him a share of the Nobel Prize in Physics in 1903, which he received alongside Marie Curie and Pierre Curie. Becquerel's experiments with uranium salts revealed that they emitted rays that could expose photographic plates, leading to the understanding of radioactive decay. Becquerel's contributions to science were pivotal in advancing our knowledge of atomic structure and radiation. His discovery not only opened new avenues in physics but also had significant implications for medicine and energy, influencing fields such as nuclear medicine and nuclear energy.