Let us explore the immune system together in a step-by-step fashion to untangle its many mysteries, components, and functions. Second only to the brain in complexity, this life-saving system protects us on a daily basis from a world of threats, including viruses, bacteria, fungi, parasites, and toxins. Some of the topics we will cover include innate and adaptive immunity; the major organs, cells, and messenger molecules involved in immune function; and how the immune system distinguishes between “self” and “non-self.” Knowledge is powerful if it leads to appropriate action. The better we understand the workings of our immune system, the better we can support its function and not weaken it. This is especially important right now with all the confusion surrounding COVID-19 and the other infectious diseases out there. This introductory science-based Zoom course will use colorful and easy to understand slide presentations and lectures, and some discussion with questions and answers.