What is the distinction between parasites and predators?

From the text:

A virus is a parasite. It can’t live on its own. It can only make copies of itself inside a cell using the cell’s materials and machinery to get the job done.

The more one contemplates the hot viruses, the less they look like parasites and the more they begin to look like predators. It is a characteristic of a predator to become invisible to its prey during the quiet and sometimes lengthy stalk that precedes an explosive attack.