The Trojan Virus gets its name from the Trojan horse of Greek myth, which is of course one of the more well known stories. In the Trojan horse myth an attacking army offers the enemy a gift of a Trojan horse, which is allowed past the castle gates, once inside the horse opens to reveal enemy soldiers who proceed to slaughter the enemy from the inside. In a much less dramatic fashion this is how a Trojan virus infects your PC: you install a seemingly useful or benign piece of software, but what's really happening is that you are installing a malicious Trojan virus, which may do anything from data mining to actually destroying data on the infected users PC.
There are two common ways a user may get themselves infect with a Trojan virus. One is to click on one of the many pop-up windows they may encounter while surfing the web: usually these windows will inform the user of a supposed error or problem with the PC and offer to fix it with a click of a button. When this button is pressed the Trojan virus is often installed. Another common way is for the Trojan virus to masquerade as a legitimate tool or application, often, ironically, a small virus removal tool. As soon as the application is run, of course, the Trojan virus is activated and the user is subject to whatever malicious damage the virus may be designed to cause.
Trojan removal can be accomplished in two ways, depending on what stage on infection the user is at. The easiest way to avoid Trojan removal all together is to simply have good antivirus software installed, and to make sure it is running and is properly up to date. A free antivirus package like AVG antivirus will work well, as will Symantec's commercial antivirus software, or the NOD32 system, which boasts an extremely low memory footprint.
If, for one reason or another, the user finds themselves already infected with a Trojan virus, they then need a Trojan remover. Fortunately, in most cases once a Trojan virus has become prevalent on the internet a specific Trojan remover is usually released to combat it. By visiting a site like Symentec or Mcafee a user can usually find a specific Trojan remover for the Trojan virus he or she has been infected with. In the best cases, the user simply has to download the small Trojan remover application and run it. In some instances, the user may find it necessary to follow some more complicated instructions given on the website for removal of the specific Trojan virus. This will usually involve using the regedit function to remove certain registry keys from the operating system. In most cases, the instructions will be very clear and step by step and even a novice user should have no problem executing the Trojan removal.
To prevent the hassle of having to do this, however, it is crucial for every user to have up to date antivirus software installed and running properly. With antivirus software in place Trojan viruses should pose little problems for most users. When this is combined with common sense when surfing the internet (i.e. don't click YES to things that seem unfamiliar) most users will find the risk of being infected with a Trojan virus extremely small.