Here's a breakdown:

* DNA (or RNA): The genetic material of the virus, containing the instructions for making more viruses.

* Capsid: A protective outer shell made of proteins that surrounds the genetic material. It helps the virus attach to host cells and protects it from the environment.

Some viruses also have an envelope made of lipids (fats) and proteins. This envelope is derived from the host cell membrane and helps the virus enter new cells.