James Clerk Maxwell

Maxwell unified electricity, magnetism, and light into a single theoretical framework with his four Maxwell equations, published in 1865 — one of the greatest intellectual achievements in physics. His work predicted the existence of electromagnetic waves travelling at the speed of light, which Heinrich Hertz later confirmed experimentally and which led directly to the invention of radio, television, and wireless communication. Einstein credited Maxwell's electromagnetism as the starting point for his own theory of relativity.