A virus infects a computer just like a biological virus would infect a plant or animal. It causes sluggish performance, can corrupt or delete data, or even render your entire computer useless, in which your only option is to erase the entire hard disk (called formatting the hard disk) and install the operating system again.

 

Anti-virus programs are one of the best ways to keep your computer safe from accidentally trying to open an infected file. There are literally thousands of viruses out there, and unfortunately more are being developed all the time. A virus scanner is one way to help keep out the bad stuff. An anti-virus program is always running in the background, scanning each file you use as well as incoming and outgoing Web traffic. It is designed to recognize any unusual file extensions or file structures that could potentially harm your computer.

 

Anti-virus software needs to be regularly updated to be most effective. Luckily, nearly every anti-virus program is designed to search for updates as soon as an Internet connection is detected. There are many different programs available, some which are free and some which you need to pay a monthly or yearly fee to use. Most anti-virus programs are designed to scan your entire computer for viruses once a week.