The most common method of inducing virus into any computer or network is to present it in form of a useful program or information. It is just like gift wrapping a bomb. Similarly, a virus maker would make and hide the virus in anything that looks attractive or compelling. Let us take a quick look at virus propagation basics and virus infection from different sources.
While email attachments are a good source of virus infection, other most common methods of virus infection are downloads from any Internet site or FTP site. Even as most websites take care that the downloadable programs are free from any kind of infections, malicious programmers get around the catch.
Virus infections can also be invited by clicking on links on your networking sites or other websites that claim to do something very good for you. For example, there was a link circulating on Orkut that claimed to show you excellent methods of SEO (Search Engine Optimization) on a video. In a world where everyone wants to get ahead of others, why would anyone share his/her secrets by offering a direct link to the secrets? A little caution combined with common sense will save you from potential virus infections.
Other methods used for virus propagation are links to websites with malicious scripts. The site may look like a genuine and clean website. However, the intention of the website is to infect your computer by sending virus or any other malware to your computer. While you are exploring the site, it may be running some script in the background that downloads malware to your computer. There are plenty of ways to check virus propagation through this method, briefed in the next section.
Among other sources of virus infections are infected removable media. These include CD and DVDs, USB Mass Storage Devices, and even cell phones. You need to be cautious while dealing with removable media.
The next sections take a look at putting a stop to virus infections and virus propagation through the methods mentioned above.