Strictly speaking, a virus adds its code to other executables to infect them (and thus spread), such that the virus code runs when the infected program(s) are run. Often, the term "virus" is used in a less formal context to mean any kind of malware, including viruses themselves as well as worms, trojans, etc.
Viruses has a charateristics of being alive but they are NOT since they are single-cell organisms.
How do you say Charateristics?
face
bacteria
peaceful
no tail
this is a good site
A vertebrate has a spine.
solid
liquid
one characteristic is that they have broad leaves
it has no characteristics of any kind