Virology is the study of viruses and viral diseases. It encompasses the structure, classification, replication, evolution, and pathogenesis of viruses. Virologists study how viruses infect host cells, replicate, spread, and cause diseases in humans, animals, plants, and other organisms. Research in virology also focuses on developing vaccines, antiviral drugs, and diagnostic tools to prevent and treat viral infections. Overall, virology plays a crucial role in understanding and controlling viral outbreaks and pandemics.