I spend most of my time these days investigating the uglier side of digital life—examining the techniques, tools, and practices of cyber criminals to help people better defend against them. It’s not entirely different from my days at Ars Technica, but it has given me a greater appreciation for just how hard it is for normal folks to stay “safe” digitally.

Even those who consider themselves well educated about cyber crime and security threats—and who do everything they’ve been taught to do—can (and do!) still end up as victims. The truth is that, with enough time, resources, and skill, everything can be hacked.

The key to protecting your digital life is to make it as expensive and impractical as possible for someone bent on mischief to steal the things most important to your safety, financial security, and privacy. If attackers find it too difficult or expensive to get your stuff, there’s a good chance they’ll simply move on to an easier target. For that reason, it’s important to assess the ways that vital information can be stolen or leaked—and understand the limits to protecting that information.