With the spreading of virus and malware on the Internet, you may suddenly find that your files deleted, your personal information lost or your software corrupted without your permissions. Now, there are four methods to guard your PC against viruses, cloud-based antivirus, firewalls, on-line scanners and antivirus software. Malware is evolving faster than ever, so it’s reassuring to discover that the latest generation of antivirus is better equipped to handle this rapid pace of change. While, we can see that there are many vendors who produce anti-virus software, and deciding which one to choose can be confusing,so what are the best antivirus softwares? In general, antivirus software works in two forms: automatic scans and manual scans. Most of the software allows users to configure it to automatically scan specific files or directories and prompt users at set intervals to perform complete scans. It is also recommended to manually scan files you receive from an outside source before opening them. Though their functions are similar, there are some aspects we should take into consideration in order to choose the best antivirus software for your PC. The first thing you have to think about is your operation system. Different antivirus software works for different OS. Make sure your antivirus software version isn’t lower than your OS. Meanwhile, if you are really concerned about security and you are still running Windows 7, you can consider upgrading your antivirus software to the version for Windows 8. Unlike the choice of other software, say, the password recovery tools which may work well Windows 2008 password recovery may be useless for Windows 8 password reset. It is supposed that Windows 8 anti-virus software may be more powerful than that for Windows 7. The next step is to check the major certifications and testing agencies to see how the antivirus scanners fare. Agencies include VB100%, AV-Test, AV-Comparatives, Checkmark, ICSA Labs, and NSS Labs. Any reliable antivirus scanner should be listed by most of these antivirus testing agencies. Besides, the price of the software matters. There is a misunderstanding that commercial tools are more powerful than free ones. Actually, we can also find many useful free tools to satisfy our daily demands. Besides, for different users, their requirements may differ a lot. Some may used the PC mostly for Internet surfing, and others may for games, videos or stocks. For example, a gamer will appreciate antivirus software that recognizes when games or media are being played and suppresses any non-essential alerts or activities. This year, some AV packages come with tie-ins to so-called cloud services, in which fresh information on new threats pushes down from the vendor’s web servers to your PC. If you need to use your PC for some confidential works, you can consider choosing this kind of antivirus tools. In fact, there are other factors can be taken as your basis. For some users, especially some computer newbie, they may also count on antivirus software to be easy to install and use. And when you examine help and support, make sure whether you need 24/7 access to technical support or whether you can make do with fewer hours. Mike Leo is an edtior writing on Windows software including password reset software, antivitus software, and any other software needed to secure Windows operation systems. He is now living in Washington and also runs a small publishing house with his friend.