VIDEO: How to protect your data on Facebook

(WAFB) - Facebook CEO Mark Zuckerberg has apologized after a voter analytics firm got its hand on the data of about 50 million users.

A Cambridge University researcher apparently made an app that asked Facebook users to take a personality test. What people didn't know is that the test opened the door to their personal information and their friends' information.

The researcher reportedly collected the data and sold it.

That's scary, but what's scarier is the researcher behind that test said he's just one of thousands of apps that do the exact same thing.

We created the video above to show you how you can change your app permission settings to protect your personal information.

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