Public health impacts all of us, in every corner of the globe, every day of our lives — not only our health and safety, but also how we live, what we wear, what we eat, what happens to our environment and the stewardship of our planet. For better or worse, these 100 objects have made their mark on public health. Some, such as vaccines, have helped keep us healthy. Others, including cigarettes, have made us sick. Some are surprising (horseshoe crabs?) and others make perfect sense (bicycle helmet). Some are relics from the past (spittoon) and others are products of our digital age (smartphone). We’ve compiled this list of 100 objects to recognize the Centennial of the Johns Hopkins Bloomberg School of Public Health — and to help us appreciate the vast reach of public health.