Note to new Linux users: No antivirus needed
One of the most common questions I hear new Linux users ask is "What program should I use for virus protection?" Many of them lose faith in me as a source of security information when I reply, "None." But you really don't need to fear malware on your new platform, thanks to the way Linux is built.
It's no wonder, then, that when Windows users are finally able to break their chains and experience freedom on a Linux desktop, they stare at me in disbelief when I tell them to lay that burden down. They are reluctant to stop totin' that load. They have come to expect to pay a toll for a modicum of security.
I try to explain that permissions on Linux make such tribute unnecessary. Without quibbling over the definitions of viruses and trojans, I tell them that neither can execute on your machine unless you explicitly give them permission to do so.
Permissions on Linux are universal. They cover three things.