What are the functions of innate immunity?

Innate immunity serves as the initial response of the immune system to harmful foreign substances, such as bacteria or viruses that enter the body. Certain immune cells (e.g. macrophages) can rapidly detect and attack these invaders in an effort to eliminate them. Another function is the detection of pathogens. Innate immune responses are activated by the body's ability to detect common features of pathogens that are distinct from those found in healthy host cells. These features include various molecules present on the surfaces of microbes, as well as double-stranded RNA molecules found in certain viruses. Another function of innate immunity is that it triggers inflammation in response to infection or tissue injury that leads to cell death.