Which discipline is William Phelps Eno, shown in the picture, considered the 'father of'?

William Phelps Eno (1858 – 1945) was an American businessman responsible for many of the earliest innovations in road safety and traffic control. He is sometimes known as the "Father of traffic safety", despite never having learned to drive a car himself.

He was born in New York City, the youngest child of Amos R. Eno and his wife, Lucy Jane Phelps, daughter of Elisha Phelps. He attended Hopkins Grammar School in New Haven and Williston Academy, and graduated from Yale University in 1882, where he had been a member of Skull and Bones. Eno died of bronchopneumonia, and is buried in Center Cemetery, Simsbury, Connecticut.

Among the innovations credited to Eno are traffic regulations: the stop sign, the pedestrian crosswalk, the traffic circle, the one-way street, the taxi stand, and pedestrian safety islands. His rotary traffic plan was put into effect at Columbus Circle, New York City, in 1905, at the Arc de Triomphe in Paris, 1907, Piccadilly Circus in 1926, and the Rond Point on the Champs-Élysées in 1927.