“What is a Primer?” Primer, n. – An introductory review article – covering one disease or disorder – that describes global epidemiology, molecular mechanisms, diagnosis and management. Primers are invaluable tools that provide a detailed introduction to a topic for those in research and medicine. They highlight both the achievements and what the most important need to know facts are in a medical topic. The Primers cover a diverse range of medical topics, everything from malaria to opioid use disorder, and everything in between. PrimeViews on the other hand are visual, illustrated summaries of an actual Primer in the form of a poster. Find out more about these Primers and PrimeViews in this dedicated virtual issue, that brings together a selection of content from Springer Nature. Click here to access the free articles.