First, let's lay some ground work. Spyware and virii (viruses) are both unwanted software. Very clever software to be sure, but still, just software you don't want.

They have been different with respect to one point: spyware is usually not destructive to the host computer or the data. Virii are usually destructive.

Spyware typically does not destroy data or the contents of the hard drive. It does spy on the user, and the user's activity. It collects information about you and sends it elsewhere (referred to as "home"). In doing so, it may make the computer unusable because it consumes so much of the computers resources. Some spyware will actually open the door to your computer, thus enabling additional spyware to invade your life.

What does spyware do, you might ask? The answer depends on the category of the spyware. A short explanation follows.

Adware
Adware is usually annoying to the user. This includes popups and popunders. They may or may not be activity specific.

Dialers
Dialer programs are both legitimate and illegitimate. Legitimate dialers are used by those users who use the telephone lines to connect to the internet. Illegitimate dialers will attempt to dial a specific phone number, or set of numbers, the user does know. Many of these will invoke toll charges on the dialing phone number without the user being aware. These can be very expensive.

Keystroke Logger
Keystroke loggers also have both legitimate and illegitimate uses. Legitimate uses include being used by a business to ensure computer user's productivity and security purposes. Illegitimate uses are usually to record the user's information without the user being aware of the action. The information targeted may include banking information, passwords, email addresses and credit card information. This information is then sent "home".

Malware
Malware describes some spyware which tends to be destructive, similar to a virus. Some examples of Malware might include some Trojans and software which cause "denial of service" problems. Spyware in this category usually cause the computer to become unstable.

Browser Helper
These small segments of code are "installed" in the browser being used to access the internet. In addition to consuming some memory, they can cause the user to be sent to an undesired web site. Some toolbars fall into this category.

Remote Administration
This is another category which has both legitimate and illegitimate uses. Many computer technical support operations use this type of software to assist computer users with problems they encounter. However, an attacker can use the same software to take over the target computer.

As you might expect, spyware is detected and removed by an antispyware program. Antivirus programs are used to block and remove virii. Please note that antivirus software usually does not detect, or remove, spyware. And, antispyware software does not block, or remove, virii. That having been said, some spyware in the "Malware" category may be detected by antivirus software. However, the software may not be able to remove it.

Speaking of antivirus and antispyware software, there are many of them available. Some software which claims to be antispyware software is actually spyware. Some of the software in both categories is so weak as to be ineffective. This creates more of a problem because it gives the user a false sense of security.

Some of the antispyware tools available consume so much of the computer's resources (memory and cpu cycles) they cause as many problems as the spyware they attempt to block. This will cause the user to disable the antispyware software, which then opens the computer to infection. The same is true for many antivirus programs.

"Internet suites" are notorious for being resource hogs. However, they don't do a good job of protecting the computer from virii or spyware. In addition, many claim to be spam (unwanted email) blockers as well. Again, these tools are not worth the money spent on them. Especially since the same functionality is usually available for free, or much less money.

The flippant answer is to disconnect your computer from the network. Notice I said network, not internet.

Yes, as long as your computer is connected to a "network" it is susceptible to being infected by spyware and/or virii. The internet is actually just an extension of your network. So, if your network has an internet connection, and your computer is attached to the network, your computer is susceptible to infection or attack.

Your objective in this brave new internet world is to minimize the damage inflicted by spyware and virii. It will come. This is why you should have antispyware and antivirus software running on your computer. You should also practice "safe computing".

What is "safe computing"? You don't open email from unknown senders. You certainly don't open attachments to email from unknown senders. You verify that an attachment to an email from a known sender is valid. The sender did in fact send it. You don't visit web sites which are "risky".

Risky web sites are not just the ones you would expect, such as porn sites. Web sites frequented by people looking for "warez" are usually heavily infected. Oh no! Another buzz word!

Warez is pirated software of all kinds. There are many web sites which provide the ability to download almost any software published which has been pirated. However, there is a very high risk of either the downloaded file being infected, or, acquiring an infection just by visiting the site.

Pirated music sites are a favorite of the adolescent and young adult groups. Included here are P2P file sharing software popular with these groups. What is unknown to most in these groups is that the software opens a backdoor to the internet. That is how the sharing is accomplished.

People who write and distributed the unwanted software know how sharing software works. In some cases, they wrote it. They just take advantage of it.

So, now what? The only safe computer is not connected to any other computer via the network or the internet. It also is not subjected to having floppies or CD's inserted into it's various devices. However, this is not practical in the internet world.

What to do?

FIRST, install known antispyware software. What software?

Spybot Search and Destroy
This one is free for the download. Send the author payment if you wish. Very good as a blocking tool and light weight enough to be used online. It will run on Microsoft platforms from 98 forward.

Microsoft Defender
This one is free for the download. Very good as a blocking tool and light weight enough to be used online. This one will only run on XP and Vista. It will not run on systems which have not been certified as "genuine" by Microsoft.

Adaware
Notice the second A. It is Ad_A_ware. There is a free and paid version. The free will only remove spyware and must be run manually. The paid version has been too resource intensive to use as a blocker.

I personally use all three. Spybot and Defender run all the time. Since I occasionally get some random piece of spyware, I use Adaware to scan the disk for anything which may have been missed by the other two.

SECOND, install known antivirus software which works.

There are two categories here. Paid and free.

For the free stuff look for

AVG
I have used this one in the past. There is also a paid version. The free version works well at catching virii and there are only a couple of features which are only available with the paid version.

Avast
I am currently using this one. . There is also a paid version It works very well. The only feature not available with the free version is the ability to run it on a schedule within Avast. However, this can be accomplished by using the Windows Task Scheduler.

The paid stuff has short free trial periods. You still have to pay.

The first on this list is Invircible, from Invircible . This is not for the faint of heart. However, I have used it since 1994 and have yet to see a virus get past it. It was one of the first, if not the first, to use heuristics.

Another good one is NOD32. Again, not for the faint of heart. I have very good experience with NOD32. However, it's track record is not a long as Inviricble.

Notice I did not mention how much any of these cost. Just that you will have to pay for them. If you try to scrimp on the cost of these tools, you will get what you pay for. Remember, it costs less to protect your data than it does to recover it.

THIRD, use them.

Schedule the tools to scan the disk(s) at night. After all, you are not using the computer. Be sure to check for updates before running. Allow the tools to run while you are using the computer. Add memory to the computer if needed.

FOURTH, be very careful about what you open in email. Only download files and music from known safe sites. Practice safe computing.

FIFTH. Configure the software. Spend some time studying the software and how it works. Get to know it. Sleep with it. It only bytes the bad guys.

All of this software requires proper configuration. That topic is beyond the scope of this diddy. I have seen the install package downloaded on the desk top and the owner thought they were protected. I have seen other techs install the software and quit. And, they thought they were done.

Learn the tool. Use the tool.