1. DNA Viruses – Viruses that have DNA as their genetic material (e.g., herpesvirus, papillomavirus).
2. RNA Viruses – Viruses that have RNA as their genetic material (e.g., influenza virus, HIV, coronavirus).
3. Retroviruses – A type of RNA virus that uses an enzyme called reverse transcriptase to convert its RNA into DNA (e.g., HIV).
4. Bacteriophages – Viruses that infect bacteria (e.g., T4 bacteriophage).
5. Animal Viruses – Viruses that primarily infect animals (e.g., rabies virus, smallpox virus).
6. Plant Viruses – Viruses that infect plants (e.g., tobacco mosaic virus).
7. Oncoviruses – Viruses that can cause cancer (e.g., human papillomavirus (HPV), hepatitis B virus).
8. Emerging Viruses – New or previously unrecognized viruses that have become a health threat (e.g., Zika virus, Ebola virus).