Viruses are wonderful parasites that replicate and propagate within their host systems. Due to their host relationship, structural properties, and genomic structure decision, they can replicate in different organisms. The virus replication cycle involves steps like attachment, penetration, uncoating, genome replication, transcription, translation, assembly, and release of offspring virions. The viral families exhibit different methods to overcome these replication stages and show diversity and capacity to adapt to variations in their genetic makeup. RNA viruses often rely on enzymes made by viruses to copy RNA in the cytoplasm. On the other hand, DNA viruses use the DNA polymerases of the host (desired) in the nucleus. Retroviruses use reverse transcription to incorporate their genome into the DNA of their hosts. This book chapter gives a full survey of the diversity of viral replication strategies. It will highlight the differences between viral families and their dynamic interaction with their hosts. A complete understanding of viral replication strategies will help design and develop novel diagnostic tools, as well as antivirals and candidate vaccines.