A photo circulating online of Facebook CEO Mark Zuckerberg's personal laptop has ignited a conversation about data security. The photo shows a smiling Zuckerberg sitting next to his laptop. His computer's camera and microphone are covered with tape. Tape? Yes, tape. Covering a computer's camera doesn't protect the device from being hacked, but it does prevent a hacker from being able to see whatever the camera sees. Covering a laptop's microphone can muffle the audio enough to prevent a hacker from listening in, uninvited. Security experts say it's not paranoid - it's good sense. A hacker can get access to your entire computer, without your knowledge, relatively easily. [Security professional Dave] Lewis said he's been able to breach a system and take control of a person's laptop camera without their knowledge. And it doesn't even always trip the light that shows the camera is live," he added. Unsurprisingly to many, women tend to be targets for this kind of hacking. It's more common than we think, said John Scott-Railton, a senior researcher at the ... University of Toronto. Scott-Railton said this practice is called "ratting," adding sometimes hackers will trade access to hacked computers. He said the same kind of software used to hack women's webcams is used to hack political dissidents, members of activist groups, and journalists. "These are people that are regularly targeted by different hacking groups because of their work. We have evidence that they're spied on through their webcams," he said.