When Centers of most cities became business areas after the invention of what?

Centers of most cities became business areas after the invention of the automobile. The automobile facilitated greater mobility, allowing people to commute easily to work and access services, which led to the development of commercial zones. Additionally, the rise of the shopping mall and suburban development shifted retail and business activities away from traditional downtown areas, further transforming urban centers into bustling economic hubs. This shift was also supported by infrastructure improvements, such as highways and public transportation systems.