Innate immunity is also known as 'natural' immunity.
It is present since birth and is the first line of defense against pathogens.
Innate immunity provides a rapid response to invading pathogens and cellular damage, taking only a few seconds to a few hours to become evident. The non-specific defense of innate immunity works does not depend on the type of pathogen present and does not change with exposure there is not memory element as there is in the adaptive* immune response.
Key players of the innate immunity repertoire include circulating macrophages and natural killer cells. Innate immunity does not have immunological memory.