Traffic safety is the interdisciplinary field of study dedicated to understanding the factors contributing to traffic crashes and developing strategies to prevent them and minimize resulting harm, particularly fatalities and serious injuries. It systematically investigates the complex interactions among road users, vehicles, infrastructure, operational controls (such as speed and traffic management), and emergency response within the transportation system, often adopting a systemic perspective like the Safe System approach, which recognizes human fallibility and aims to create a resilient and forgiving environment for all road users. This field is critical for developing evidence-based policies, standards (such as those for traffic control devices), and interventions aimed at achieving ambitious goals like zero traffic deaths.