Do Apple devices need anti-virus software? The nature of cyber attacks is changing, and traditional perimeter defenses aren't as effective as before.

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Free Antivirus Software: Top free, legal PC and Mac

"Windows Defender helps you stay productive by protecting your computer against pop-ups, slow performance and security threats caused by spyware and other potentially unwanted software." as for your other "form of Norton scan", that could be anti-virus, or anti-spyware, or anti-rootkit, or