Learning About Computer Viruses
The internet has transformed computers from mere word processors and gaming devices into platforms that can be used to access content from across the entire globe, a process that has become increasingly effortless over the years. Now, finding information on nearly anything imaginable is as easy as typing a word or two into a search engine.
Unfortunately, there is a flipside to the benefits of the open-ended and easily accessible nature of the internet. Viruses - malicious, potentially harmful software with the ability to reproduce and spread from system to system - infect millions of computers each and every day, oftentimes without their users even noticing it.
At the most basic level, a virus is simply a program designed to do any number of things, the majority of them undesirable to the user of the system that the virus seeks to infect. Sometimes, the goal of the virus' programmer is simply to spread the program to as many computers as possible without doing any real damage. Of course, as with biological viruses, this is not always the case. Many viruses are harmful, creating an unfathomable host of problems. These can range from the deletion or corruption of certain files to catastrophic damage to an operating system that, in some instances, can render it unusable.
Unlike other forms of malware, a virus is distinct in the sense that it spreads through replication. Most of the time, a virus is attached to an executable file (.exe file extension) that a user would have some reason to open. When the user opens the executable file, the virus begins its gruesome work. Some viruses proactively throughout a system, locating and infecting files, while others store themselves in the operating system's memory and infect files as the user activates them. Either way, a virus can propagate very quickly and in many places. Viruses are especially dangerous for users with networked machines, as some will seek to infect files shared by other computers on the network and infect them all at once.
While all of this might sound very daunting, there is no reason to panic. Keeping your computer virus-free is much easier than you might think. Here are a few things to keep in mind:
Be careful! Simply avoiding situations that seem risky to your computer's health will tremendously reduce the chances of being infected with a virus. Since viruses in particular tend to spread by way of executable files (those ending in .exe), it's very important that you be sure of any .exe file's authenticity before running it. Of course, if you want to be absolutely certain...
Run a virus scan! There are plenty of programs out there that can check both your entire hard drive and individual files for infections that they can then usually remove. While there are plenty of paid, subscription anti-virus programs that are more than up to the task, there are free alternatives as well, such as Malware Bytes' Anti-Malware and avast! anti-virus:
Finally, your computer can't be considered truly safe unless you've got some kind of firewall or equivalent safeguard in use. Firewalls protect your computer from external attacks. That is, they can stop someone or someone's malicious programs from exploiting security holes in your internet connection (which, for the average cable and DSL user, can be numerous) to gain access to your computer and install all kinds of undesirable things, including viruses. A decent firewall will halt most attackers dead in their tracks. Windows XP and Vista both come with a generic firewall. Most experienced malware fighters, however, will likely recommend something more sophisticated. There are plenty of free options, such as ZoneAlarm and Comodo (a favorite amongst many internet users):
Of course, if the above methods aren't enough to resolve a virus issue, one can resort to other methods such as a system restore (returning Windows' system files to an earlier date), a re-installation of the operating system, or a format and a clean wipe of the entire hard disk.
Luckily, most users will be able to avoid any drastic measures by taking the above suggestions to heart and using common sense. Nonetheless, it's always wise to keep important files backed up somewhere, just in case, and to always have your PC's health and security in mind.