There are two main types of immunity: innate immunity and adaptive immunity.

1. Innate immunity is the body’s first line of defense against infections. It includes physical barriers such as the skin and mucous membranes, as well as cellular and molecular defenses such as phagocytes (white blood cells that engulf and destroy invading microbes), natural killer cells (cells that destroy infected or cancerous cells), and the complement system (a group of proteins that work together to destroy pathogens).

2. Adaptive immunity is a more specific and targeted response to infections. It involves the production of antibodies and the activation of T cells, which are white blood cells that recognize and respond to specific pathogens. Adaptive immunity is highly specific and can “remember” previous infections, providing long-term protection against future infections with the same pathogen.

Both innate and adaptive immunity are important for protecting the body against infections and maintaining overall health.