Why Mark Zuckerberg covers his laptop's camera and microphone

Is taping your laptop a necessary security precaution? The chief executive officer of Facebook apparently thinks so.

When Mark Zuckerberg, the chief executive officer of Facebook, posted a photo celebrating Instagram's latest user numbers, he piqued interest in another matter entirely: online privacy.

The image revealed a surprisingly makeshift security precaution against hackers. The world-class coder and co-founder of the world's largest social network apparently covers both his laptop camera and microphone jack with tape.

Twitter user Chris Olsen spotted Mr. Zuckerberg's tape-adorned laptop in the background of the photo he posted Tuesday. The laptop does appear to really belong to Zuckerberg – it's sitting on the same desk he showed off as his own in a Facebook live video office tour.

Is taping your laptop a paranoid move or a common-sense security precaution?

"I think Zuckerberg is sensible to take these precautions," Graham Cluley, an online security expert and consultant, wrote in an email to The New York Times Wednesday. "As well as intelligence agencies and conventional online criminals who might be interested in targeting his billions, there are no doubt plenty of mischievous hackers who would find it amusing to spy upon such a high-profile figure."

Even the director of the FBI, James Comey, revealed he puts tape over his personal laptop's camera – though he didn't elaborate on its utility in his offhanded comment. "Because I saw somebody smarter than I am had a piece of tape over their camera," Mr. Comey said in response to a question at Kenyon College in April, as NPR reported.

The taped-over camera and microphone jack are intended to protect against hackers using your laptop camera to take surreptitious pictures or videos or accessing your microphone to eavesdrop on conversations – a possibility once your device has been accessed through "ratting."

"Ratting" refers to the use of a remote access trojan (RAT), which is a software that allows someone to remotely control a computer. They're usually sent as an email attachment or downloaded alongside an innocuous program, like a game.

Once the RAT has enabled administrative control, it can activate a webcam or microphone – without illuminating the indicator light – in addition to other snooping including accessing credit card information and taking screenshots.

Basic security precautions can be taken against "ratting" include updating software regularly, installing anti-malware software and a firewall, and not clicking suspicious links.

Simple moves, including using a different password for every site, can prevent security headaches, as Zuckerberg has learned. Hackers briefly took control of his Twitter and Pinterest accounts, claiming they used the password made public in a database of passwords hacked from LinkedIn in 2012.

But Mashable reporters refuted the tape-covered microphone trick and found neither clear tape nor thicker gaffer's tape to effectively reduce the microphone's audio pickup, even with a second layer. Mashable recommended a slightly more complicated approach, instead, involving headphones and a pair of scissors.