The last two decades have experienced the outbreaks of three different coronaviruses in the different parts of the world namely; Severe acute respiratory syndrome cornonavirus-1 (SARS-CoV-1), Middle East respiratory syndrome (MERS-CoV) and Severe acute respiratory syndrome cornonavirus-2 (SARS-CoV-2). We aimed to delineate the differences in viral dynamics and clinical features between them and tried to focus on every basic details of SARS-COV-2 (COVID-19) that every health care provider must know.We systematically searched the PubMed database up till April 2, 2020 and retrieved all the articles published on SARS-CoV-2, SARS-CoV-1, MERS-CoV that dealt with viral dynamics.Ample data is available to suggest the differences in etiology, transmission cycle, diagnosis, genetics, hosts, reproductive rates, clinical features, laboratory diagnosis and radiological features between SARS-CoV-1, MERS-CoV and SARS-CoV-2.Although SARS-CoV-2 (COVID-19) is more infectious than SARS-CoV-1 and MERS-CoV, most infections are generally mild and self-limiting. However, case-fatality rates are very high in patients with COVID-19 with comorbidities, compared to SARS-CoV-1 and MERS-CoV.