Traditional computer viruses emerged in the 1980s, driven by the spread of personal computers and the resultant increase in BBS, modem use, and software sharing. Pc viruses are very common these days and can easily be spread by attachments in e-mail messages or by instant messaging messages. These viruses can be disguised as attachments of funny images, greeting cards, or audio and video files. Pc viruses can also be spread by using downloads on the Internet and can be hidden in pirated software or in other files or programs that you may download.
Often this type of software is referred to as Malware which includes computer viruses, worms, Trojan horses, most root kits, spyware, dishonest adware, crimeware, and other malicious and unwanted software), including true viruses.
Malware such as system viruses and worms can be very harmful and damaging to your computer system, root files, and various program files. PC viruses and network worms have evolved through a continuous series of innovations, leading to the recent wave of fast-spreading and dangerous Pc worms. These computer viruses and worms are characterized by their ability to self replicate. These viruses replicate themselves by attaching their program instructions to an ordinary "host" program or document, such that the virus instructions are executed during the execution of the host program.
Worms and Trojans, like viruses, may cause harm to a computer system's hosted data, functional performance, or networking throughput, when they are executed. Worms are more complex than Trojan viruses, and usually attack multi-user systems such as UNIX environments and can spread over corporate networks via the circulation of emails. Worms increase in prevalence with Sircam, CodeRed, and BadTrans creating the most problems.
Windows Operating system
Windows has the same type of scripting ability as Unix-based systems, but doesn't natively block normal users from executing such scripts written by a third-party as UNIX / Linux does for users who are not running as root. Windows will not start at all, even though you have not made any system changes, or you have not installed or removed any programs. Windows will not start because certain critical system files are missing, and then you receive an error message that lists those files. This is one reason why Linux based OS are much more secure a good popular example is Apple Mac OS which is Linux based.
Antivirus software may be used to detect and remove viruses from a computer, but the software must be updated frequently for protection against new viruses. Antivirus software can be used to detect and destroy well-known viruses, but new viruses continually appear and these may bypass existing antivirus programs. Antivirus programs must be updated continuously to look for new and modified viruses. Some viruses try to avoid detection by killing the tasks associated with antivirus software before it can detect them.
Computer viruses can be very harmful and damaging to your computer system, root files, and various program files. PC viruses and network worms have evolved through a continuous series of innovations, leading to the recent wave of fast-spreading and dangerous worms and come in many forms and can cause various kinds of damage to your system.
What to do when obtain computer virus and security-related issue occurs? Well before contacting support, follow these steps: make sure that you run updated antivirus software and updated spyware removal tool on the infected computer. You can also research the virus either at Symantec or MacAfee or related sites and if all else fails then it is time to contact a support engineer to help you with the issue before your computer spreads the harmful file.