Public health surveillance is the continuous, systematic collection and analysis of health data to monitor the health of populations. It helps identify outbreaks of diseases, track health trends, and evaluate the effectiveness of public health interventions. This process is essential for informing public health policies and ensuring community safety. Surveillance systems can include various data sources, such as hospitals, laboratories, and surveys. By analyzing this information, public health officials can respond quickly to emerging health threats, allocate resources effectively, and promote health education. Overall, public health surveillance plays a crucial role in protecting and improving community health.