Do we need to install any antivirus software on Windows 8? Because I read that Win 8 will have an inbuilt antivirus. Here's my findings on this topic. "Microsoft's Windows 8 will activate its built-in antivirus software only if it senses that the PC is not protected by another security program, according to AV vendor McAfee." "Windows 8 will activate Windows Defender only if there is no other antivirus software on the computer. Even if Windows Defender detects that existing antivirus software hasn’t been updated recently, it will only offer Windows Defender as one of several choices, and only after leaving users vulnerable for 15 days.During those 15 days, the Windows Action Center will warn users that their antivirus package has expired and offer them information on how to renew their license. Leaving users in a position where they’re vulnerable for 15 days because of no new antivirus updates when there’s a fully-featured antivirus package installed on the system seems highly negligent of Windows to me. Users have paid for a Windows license, and that Windows license buys them the right to use Windows Defender, and yet a deal struck between Microsoft and the OEMs means that consumers aren’t able to benefit from the feature they’ve paid for." So the important question is whether we should install an antivirus? If so, then which would be the best antivirus for Windows 8?