Viral DNA is the genetic material of a virus that can replicate inside a host's cell. As the study of viruses and genetic engineering advances, there are now many synonyms for the term "viral DNA." These include but are not limited to: viral genome, viral RNA, genetic material of viruses, viral nucleic acid, viral DNA/RNA hybrid, viral genes, viral coding sequence, and viral replicative DNA. These terms describe various aspects of the viral DNA that researchers are studying in order to develop treatments and vaccines for viral infections. Understanding the genetic makeup of a virus is essential in finding ways to stop its replication and spread.