Herd immunity, also known as community immunity, occurs when a significant proportion of a population becomes immune to a specific infectious disease, either through vaccination or previous infection. When enough individuals are immune, the spread of the disease is slowed or halted, protecting even those who aren’t immune. This concept is crucial in preventing the rapid transmission of diseases within a community and plays a key role in vaccination strategies. Understanding herd immunity is essential for managing and controlling the impact of infectious diseases on a broader scale.