Thomas J. Watson, Sr. was an American businessman and entrepreneur who served as chief executive officer and chairman of IBM, shaping the company across more than four decades of the twentieth century.

Born on February 17, 1874, in Campbell, Watson was educated at Columbia University before making his way into the business world. He drew on training he'd received from John Henry Patterson at NCR to develop IBM's management style and corporate culture, and from 1914 to 1956 he oversaw the company's growth into an international force. Under his leadership, IBM became a highly effective selling organization built largely around punched card tabulating machines. Watson received a number of notable honors during his lifetime, including the Medal for Merit, the Silver Buffalo Award, the Order of the German Eagle, and an honorary doctorate from the University of Grenoble.

Watson died on June 19, 1956, in New York City. His long tenure at IBM — spanning more than four decades as both its chief executive and chairman — was defined by a focus on sales culture and the organizational principles he carried forward from his earlier career. The punched card tabulating machine stood at the center of IBM's commercial identity throughout his time at the helm, and it remained the practical foundation on which he built the company's reach as an international enterprise.