I am assuming you mean "What is a virus capable of?". Viruses are capable of a lot of things, and spread by replicating themselves in their host.
I would recommend looking here:
http://en.wikipedia.org/wiki/Virus
Yes, a virus is capable of crashing your hard drive.
A specific pattern of virus codeAccording to printon.edu, a virus is" a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer; "a true virus cannot spread to another computer without human assistance""
That would be the virus.
As not all bacteria or virus are capable of living in vector(eg:insect) in other way, insects are not capable of carrying and /or transmitting all bacteria/virus.
A virus particle that does not have a host is called a "virion." Virions are the infectious form of a virus that is capable of spreading to other hosts.
A virus.
A virus.
A virus
A virus capable of spying on financial transactions, email and social networking activities
A metamorphic virus is capable of rewriting the code upon each new file infection. It'll change the code not the engine to avoid pattern recognition.
Viral Envelope
Use Kaspersky Internet Security of version 9.0+... it is capable of clearing worms