Robots and self-driving cars could deliver packages efficiently. But will they create new hazards?
Krystal Vasquez, Contributor
Violence and disease -- but also art and culture -- accompanied humanity's movement into increasingly populated areas.
Charles Q. Choi, Contributor
New theoretical models help urban planners understand how residents think about clean air.
Jennifer Leman, Contributor
Researchers discover that the arrangement of cities’ streets and buildings affect how much heat they trap.
Yuen Yiu, Staff Writer