1. Attachment ( adsorption ) of the virions to a susceptible host cell.
2. Penetration ( entry,injection ) of the virions or its nucleic acid into the host cell.
3. Synthesis of virus nucleic acid and protein by host cell metabolism as redirected by the virus.
4. Assembly of capsids ( and membrane components in enveloped viruses ) and packaging of viral genome into new virions. This whole process is called maturation.
5. Release of mature virions from the cell.