A computer virus is a piece of code (sometimes as little as 1 line, or as large as a complete program) to which is capable of copying itself and typically has a detrimental effect to a PC, such as corrupting the system, destroying data or gathering personal information.

A virus is a type of malware, which stands for malicious software — software designed to cause damage to system files, copy data, crash a computer or infect multiple devices on a network.

Often spread by attaching themselves to emails and exponentially infecting more victims, viruses are sometimes hard to identify and stop. You may have heard of the ‘ILOVEYOU’ virus, which originated in the Philippines and when sent in an email, automatically forwarded itself to every person in a recipient’s address book. As you can imagine, it very quickly spread across the internet, infecting tens of millions of computers from just the sending of an email.

One of the first and most widespread viruses ever seen, called ‘The Morris worm’, rendered a computer useless and affected 10% of all computers connected to the internet, costing the U.S Government Accountability Office an estimated $10,000,000. The worm was released from MIT and was not initially intended to be malicious, but the mechanism which fuelled the spreading of the worm caused it to be installed on computers far more than just once, which eventually caused the computer to malfunction.

The ILOVEYOU virus spread via email and the Morris worm spread through network connections, but these are not the only ways viruses can be spread — One common method hackers use to reach the public’s computers  is to mask virus downloads with names used by popular, trusted companies / government bodies.

For example, what you may think is a document from your bank may well be a virus. Another common method using trusted names and corporations is phishing scams, which prey on the naive and exploit those who do not take proper precautions when submitting personal details.

One more very deceiving way viruses get from hacker to your computer is by websites initiating downloads as soon as you visit their site. Done in the background and completely undetected, the download transfers malware to your computer. In most cases, these won’t be trusted websites which you visit every day, they are normally sites with adult or pirated content. However, there have been cases of websites being hacked and auto-downloading of malware becoming a feature of the site, so we suggest you take preventative measures to keep this from affecting you.

The best way to protect yourself from viruses is by using free antivirus, this will scan your computer regularly to make sure there are is no malware on your computer. The best free antivirus software will go further than this, protecting your data entry and PC intrinsically through use of virtual keyboards and more. Free antivirus software is offered by many of the top antivirus providers allowing you to do a full system scan on your computer for free, helping you detect any malicious software that may have found its way onto your machine. Free antivirus scans will generally be the same as a paid scan detecting all of the same viruses offering you the opportunity to find out if your computer is infected before you take the plunge and buy your long term antivirus software partner.