The Industrial Revolution transformed societies from rural to urban industrial ones in the 18th century through mechanization. Industry has since evolved through four stages - mechanization with steam/water power (Industry 1.0), automated production using computers/IT (Industry 2.0), mass production with assembly lines and electricity (Industry 3.0), and currently smart factories using the internet of things, machine learning, big data, and cyber-physical systems (Industry 4.0). Industry 4.0 impacts include changes to security, identity, and education, while benefits are reduced costs, collaboration, and competitiveness - but it also risks increased inequality and tensions. Its key building blocks are cloud computing, autonomous robots, machine learning