All About Computers: Viruses

I get a few PMs, and read a few topics about computer problems. And so, I figured instead of dealing with things on a case by case basis, I'd do my bit to educate the masses, to the best of my knowledge. As could be expected, it seems many Dogsey users aren't overly au-fait with computers, and I think that's to be expected.

I'll tackle as many areas as I can, but have elected to start with computer viruses. If you have a particular area you'd like covered, just shout, and I'll do my best to accommodate, when time permits, though with regularity, I assure you.

As a regular computer user, and programmer of many years, I've tried to be as unbiased and factual as I can be. Though, if a little bias happens to slip in, forgive me.

Computer Viruses
The bad news is that it's remarkably easy to get a virus onto your computer. The good news however, is that it's also remarkably easy to render them useless and harmless, the moment they reach your computer.

WHAT IS A VIRUS:
A virus is a piece of computer code, usually designed to act in a malicious manner. This act may not be immediate, and may, for example, be programmed to "set off" at a particular date and time.

The result of an active computer virus can be incredibly varied. It can be as relatively harmless as changing the document author's name in a Microsoft Word document, to something of intermediate effect, such as sending out the same virus to all of your email contacts, without your knowledge, to something really quite disastrous such as deleting some or all files from your computer, and even, in very rare and extreme cases, rendering your computer to just a paperweight status.

There are also "trojans" which in many cases, can act as doors into your computer, to allow people from other computers to access yours and use it to read your files and passwords, or to use your computer as a "springboard" to carry out malicious work on another computer, making it appear that your computer did it.

HOW DO I GET A VIRUS:
There are several ways of receiving a computer virus, and in fact, the methods change all the time, as virus creators and companies who exist to destroy the virus codes they create, constantly do battle with one another. As one distribution method closes, another, often more creative method is exploited. Typically however, the following are common methods of receipt:

- As a file attachment with an email or Messenger applications, such as MSN Messenger.
- Via active-x or javascript when simply looking at a website.
- Downloading files from "dodgy" websites.
- Downloading illegal or pirated files through file-sharing applications, such as BitComet.


PRECAUTIONS TO TAKE:
Aside from using an anti-virus solution, which I'll come to, there are some things which you can and should do to help keep your computer virus free.

- Do not open file attachments from people you do not know.
- Do not share your computer information on websites you cannot trust.
- Do not use websites of a more "adult" nature. They are absolutely notorious for being used as virus catalysts.
- Do not use sites which offer free passwords or free files which you would normally expect to have to pay for (such as movies or CDs, for example.)
- Do not share your email address all around the web. Do you go around the street telling everyone you meet where you live? The same applies...
- If you can avoid using Internet Explorer 6, do so. Upgrade to Internet Explorer 7, or try a different browser, such as Firefox.

HOW WORRIED SHOULD I BE:
If you believe the media, then you had better wear full body-armour at your computer, spray your computer with disinfectant every five minutes, and perhaps consider never turning your computer on in the first place. The reality however, is, I'm pleased to report, nowhere near that bad. While I don't suggest doing so, merely by following the above 'precautions to take', you'd be really quite safe if you did.

The fact is that through such things as constant browser updates it's getting much harder to distribute viruses from computer to computer.

ANTI-VIRUS SOFTWARE:
The best and usually the safest solution is to invest in software where its sole objective is to seek out viruses as they reach your computer, and delete or "disinfect" them. (Render them harmless.)

Be aware; not all anti-virus packages are created equally. The crucial things to look for when selecting the best solution for your needs are:

- Frequency of signature updates
- Speed and size, in relation to your computer.

Signature Updates:
Anti-virus software works by reading each and every file on your computer, and checking for a particular piece of code within that file for a a small extract of code which has been previously identified as a virus. Once found, it flags that file as "infected" and does whatever action it's been instructed to do. (Delete the entire file, remove the small fragment of dangerous code, or move it to where it will never be opened.)

As new viruses are created with such regularity, it's critical that you choose an anti-virus software solution that is quick to recognise these new "signatures" and send them to your anti-virus software so that it can recognise them in the first place. Without the rapid frequency, you may well get a virus which your anti-virus package simply doesn't recognise, as it doesn't have its signature. It might get it tomorrow, but by that time, it might be too late.

Signature updates are usually done automatically by the anti-virus software, though you can usually choose to collect them mnaully at a time that suits you. For the most part, it is a completely automated process, where it contacts its main server, downloads new signatures, and registers them into its existing database. Simple.

Speed and Size:
Go to any "techie" website and you'll see opinions ten-a-penny about how one anti-virus package is "crap" whilst the other is "mega". Whilst there is a degree of truth that some are better than others, it's not that simple. These "opinions, and make no mistake, that is usually what they are, and nearly always heavily biased, and often based on ignorance.

Some anti-virus packages are bigger than others, in that they require more memory to run, and this is often what these technical opinions are based upon. You will often hear the accusation "it's bloated" levied against Norton (Symantec) anti-virus, for example. Let me clarify, memory on a computer is there for using. That's its sole objective, to provide space for an application to run.

Therefore, older computers or computers where memory is scare (lower than 256MB) might gain some small benefit from avoiding the larger applications such as Norton (Symantec) Antivirus. However, if you've purchased your new computer within the last year or two, then it's a pretty safe bet that you can ignore these biased opinions. Though I would argue that at some point you're going to need to add extra memory as applications aren't getting any smaller these days, so it might be time to invest in more memory anyway.

So, which package, and which ones are available?

Some are free, and some are commercial. Commercial ones are usually based on a "subscription" basis. That is, you might receive the signature updates for a year, after which time, you might need to pay a smaller fee for the next year's worth.

The free ones, as the terms suggests, provide free updates for life. My personal opinion is that in this case free may not always be the best option, but I stress that is just my opinion. It is up to each individual to weigh the pros and cons and make the decision that best suits them.

ANTi-VIRUS SOFTWARE PACKAGES (In no particular order)

Please note that this is not an exhaustive list, and many others are available.

Norton Antivirus (Commercial)
http://www.symantec.com/home_homeoff...edom/index.jsp

Mcafee (Commercial)
http://www.mcafee.com/us/smb/product...rus/index.html

AVG (Free + Commercial Also Available)
http://www.grisoft.com/doc/1

Trend Micro (Commercial)
http://www.trendmicro.com/en/product...e/overview.htm

Bullguard (Commercial)
http://www.bullguard.com/

Active Virus Shield (Free - Please note I've never heard of this one before and so can't validate its authenticity)
http://www.activevirusshield.com/ant...eav/index.adp?

Next: Hacking - Have I Been Hacked, and How Can I Avoid It?