 117 COVID-19 vaccines are in clinical development, with major platforms including protein subunit, RNA, inactivated virus, and viral vector. The Pfizer-BioNTech vaccine has been approved by US FDA for full use in individuals aged 16 and above. However, there is an inequity in vaccine distribution as wealthiest countries have about 28 percent of total vaccines despite having only 10.8 percent of the world population. The review covers the history of vaccines, specifically focusing on SARS-CoV-2 vaccines, and discusses challenges and limitations in global vaccination efforts. This article was authored by Gaurav Joshi, Pobitrobora, Shweta Thaka, and others.