From the cellular level on up, being aware of your interactions can help you stay safe. This resource addresses fundamental immunology and infectious disease concepts through a historical exploration of immunization and the immunology of SARS-CoV-2. Key concepts include 1. Self- and non-self recognition 2. Components of the immune system 3. Innate and adaptive immune responses 4. Acquisition of immunity over time - primary and secondary responses 5. Immune recognition of viral particles - antigen presentation, T cell activation 6. Human immune responses to SARS-CoV-2 7. Herd immunity 8. Variolation and vaccination - exposure to stimulate immune response 9. History of vaccination