The Steel Age refers to a period in history characterized by the widespread use of steel for tools, construction, and machinery. This era began in the late 19th century and continued into the early 20th century, marking a significant advancement from the previous Iron Age. The development of steel-making techniques, such as the Bessemer process, allowed for stronger and more durable materials, which transformed industries and infrastructure. During the Steel Age, cities expanded rapidly, and transportation systems improved with the construction of railways and bridges. Innovations in manufacturing and engineering led to the rise of major industries, including automobiles and shipbuilding. This period laid the groundwork for modern industrial society and significantly impacted economic growth and urbanization.