Waymo, the self-driving car company, is significantly expanding its operations, launching its driverless cab services in Baltimore, Pittsburgh, St. Louis, and Philadelphia. The move includes a mix of autonomous testing and manual driving preparations as the company gears up for a public launch. In these cities, Waymo aims to introduce its robotaxi services, featuring both fully autonomous vehicles and those with human drivers during the initial phase. With this expansion, Waymo is tackling challenges in diverse weather conditions while planning to enhance its national rollout across the United States.