I’m sure you have heard this from a friend before, even some of your computer-literate friends; but what I want to warn you of is that this is a dangerous question to be asking. You for sure know about viruses and that anyone today is vulnerable to them if they haven’t taken appropriate efforts to protect themselves, but other than that (if you are like most people you don’t really know what is out there (lots more than just viruses) and how to really protect yourself properly.) In the next few paragraphs, I want to tell you some critical information to save you lots of time and money, and tears.
So viruses are, just like their biological counterpart, parasites in that they use a host to exist and more importantly to replicate. A virus is made up of computer code that is written in such a way as to insert itself into an existing code of (most often) an executable file that already exists on the host computer. It uses the internet mostly to travel but can and has been transferred by removable forms of media like floppy disks, smart cards, etc. Like viruses, worms use the computer as a host, but only in order to use the hardware, as they do not need the host computer software to replicate. Trojan Horses are another example of malicious software or malware that use techniques that evade the natural and built up defenses on a computer. The point is that there are more than just viruses that you need protection from and not all anti-virus software (especially free antivirus software) provides the comprehensive coverage that you need.
The sad thing about free anti-virus software is that it lulls computer users into complacency, and they end up as bad or worse off than when they were virus-free. The companies that offer these freebies are doing it more or less than an advertising ploy, bringing more traffic to their sales page.
Now there is a caveat to this that I would like to explain and that is that free antivirus software is better than having nothing at all. So, if you are too poor to purchase your own security software package then by all means get it on your computer. However, I seriously doubt that if you are able to purchase a computer you would not also be able to get anti-virus protection. Consider it nothing more than a necessary maintenance cost, kind of like putting oil in your car every once in a while.