The sudden outbreak of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in late 2019 has necessitated discussions on different facets of the disease. These include its transmission, pathogenesis and vaccine development. The aims of this study were to discuss the SARS-COV-2 vaccines development, mechanisms of action as well as the general acceptance of these vaccines by various countries/or people. Sequel to the outbreak, several vaccines models have been discovered with promising outcomes. Few of these vaccines have been approved for emergency use; but so far, only a small portion of the world's population has been vaccinated, which is a global problem that requires urgent intervention. Knowledge of the immune response associated with SARS-CoV-2 infection is imperative to the understanding of the mechanisms of action of these vaccines. Additional researches on some of these SARS-CoV-2 prominent vaccines have become necessary. The step-to-step development of these vaccines and their effectiveness will clear the air and increase the citizen's trust in these vaccines. Amid SARS-CoV-2 vaccine development; two DNA adenovirus vaccines were developed in the United States (Oxford-AstraZeneca and Johnson and Johnson). In addition, two other mRNA modified lipid nanoparticle vaccines were developed in Europe (Pfizer-BioNTech and Moderna). This review covered the discussion on the basic molecular mechanisms of these vaccines; with particular focus on the in vivo responses toward these vaccines recorded by the vaccinated individuals.