Since the declaration of SARS CoV-2 pandemic, we have witnessed an accelerated increase in new cases, frequently associated with the need for intensive care and mechanical ventilation. In parallel, we have been invaded by many experts in the press and who expose their knowledge on the behavior of epidemics who use concepts that are not always well understood by the medical community. Some concepts should be knowledgeable to understand the epidemic spread. First, the epidemic spread description is not modeled with an exponential curve, but rather with a Gompertz curve. Second, a gamma curve describes the period of contagiousness. Third, the contagion magnitude or rate can be calculated and modeled. Explaining these mathematical concepts in a simple and graphic way will allow readers to understand better what is happening with the current pandemic.