what is the different between virus and worm?

Answer 1

Asking this question at a convention of computer anti-virus researchers is a sure-fire way to start a fight. :-)

Seriously, there is no agreement on this subject. There are three main different schools of thought.

According to the first one (the one I also subscribe to), a worm is a kind of virus that *explicitly* uses the network to replicate itself. Note the emphasis on the work "explicitly". For instance, a virus which just enumerates all drives and infects the files on them might spread over the network if one of those drives happens to be a mapped network drive - but this doesn't count as "explicitly". Also, the kind of network doesn't matter - it could be e-mail, TCP/IP, WiFi, Bluetooth, anything.

According to the second school of thought, a worm is again a kind of virus - but one which is self-contained, i.e., which does not attach itself (infect) other executable files. That doesn't necessarily mean that it consists of a single file - it could consist of a set of several files; the important thing is that it doesn't infect other files. Personally, I prefer to call such viruses "non-parasitic", as opposed to the parasitic ones - i.e., the ones that infect other files. Furthermore, there are viruses that do not infect files (e.g., boot sector viruses, companion viruses, etc.) which, historically, have not been considered worms. While it could be argued that most of those are at least in some way "associated" with a host (even if they don't physically attach themselves to it), there are some members of these types of viruses that would work even if the "host" is absent - yet they aren't called "worms", either.

According to the third (and most exotic) school of thought, a viruses and worms are two different kinds of malicious programs (i.e., worms aren't viruses). In addition, a worm must be able to spread without any human interaction whatsoever - i.e., it has to be able to self-instantiate itself on the remote computer. According to this definition, CodeRed is a worm - but LoveLetter is not ( because the latter requires the user to click on an e-mail attachment).

The reason for this disagreement is because the term "worm" first gained wide popularity when the Morris Worm was released in 1988. That particular worm was a "worm" according to all of the above definitions; but people disagreed which of its properties made it a worm (instead of a simple virus).

Answer 2

A computer virus is a small program written to alter the way a computer operates, without the permission or knowledge of the user. A virus must meet two criteria:


* It must execute itself. It often places its own code in the path of execution of another program.
* It must replicate itself. For example, it may replace other executable files with a copy of the virus infected file. Viruses can infect desktop computers and network servers alike.

Worms are programs that replicate themselves from system to system without the use of a host file. This is in contrast to viruses, which requires the spreading of an infected host file. Although worms generally exist inside of other files, often Word or Excel documents, there is a difference between how worms and viruses use the host file. Usually the worm will release a document that already has the "worm" macro inside the document. The entire document will travel from computer to computer, so the entire document should be considered the worm W32.Mydoom.AX@mm is an example of a worm

Answer 3

A worm is a type of virus. A worm spreads by itself.

Answer 4

there basically the same but a virus needs to attach itself to a existing program as where a worm does not. and worms effect networks aswhere virus's destroy a target pc.

Answer 5

Trojans are usually tracking type programs or code that "watch" wha tyou do on your pc and try to override certain settings to divert you to wherever it is it wants you to go, and could potentially cause critical system errors by doing so. A worm is something that embeds into your system and slowly but surely can turn off or completely undo programs and operating systems. A virus is something that "infects" your computer in a variety of ways, usually causing system crashes and program errors and eventually can cause the system to become so unstable that it is rendered unuseable.

Answer 6

Virus files requires the support a exe file for its exrecution. Whereas worms can function itts own. They don't require the help of another file.

Answer 7

Virus afeects the place that it has entered. Worm slowly spreads and infects the whole system. You insatll a standard antivirus soft ware such as Norton, AVG , Avast ( free antivirus software and Ad-aware, Ewido ( free spyware removers). You can download free softwares at
http://fixit.in/antivirus.html and http://fixit.in/spywareremover.html

Answer 8

Virus attack are swift while worm eats slowly and steadily.

Answer 9

The same damn thing. Get a good antivirus program. Here you have some free options:
http://askcomputerexpert.ws43.com/download/security.htm

Answer 10

they are both a nuisance,
but not harmfull
Its like a lot of raccoons living in the trunk of your car,
You are going to kill them with your antivrus protection??
Avast if you get stuck.
http://www. avast.com/eng/programs.html
Love Ron.