Innate immunity is the first line of defence in our immune system. It is non-specific and responds to the common features on all pathogens. It is absolutely essential for survival as it creates barriers to microbial invasion and provides critical biochemical and cellular first responders to infections.
Innate immunity includes physical barriers, like our skin and saliva, as well as innate immune cells like macrophages, mast cells, neutrophils, and basophils. They are up and running in our body constantly to protect us when an infection is first encountered.