There are also different types of viruses. For example, the HIV virus, virus that doesn't only undergo the Litig cycle, it can also undergo the lysogenic cycle. In the lipogenic cycle the DNA of that virus is actually incorporated, it's integrated with the DNA of that whole cell. Now, what exactly is the main difference between the Litig cycle and the lipogenic cycle? Well, the Litig cycle isn't very useful because it actually kills off that whole cell. So once the cell dies, the virus does have to find other cells to actually infect.