Keep your data safe! Think twice before taking that Facebook quiz

The screen on an Apple Inc. iPhone displays the word 'Data ?' against a backdrop of the Facebook Inc. logo displayed on a computer screen in this arranged photograph in London, U.K., on Thursday, March 22, 2018. Facebook Inc.’s co-founder and chief executive officer Mark Zuckerberg has been called to appear before a House panel as fallout continues from revelations that Cambridge Analytica had siphoned data from some 50 million Facebook users as it built a election-consulting company that boasted it could sway voters in contests all over the world. Photographer: Luke MacGregor/Bloomberg

What kind of pizza are you? What does the kind of pet you have say about your personality? Which US city is your perfect fit? 

Quizzes like these are all over Facebook and other social networks. For kids, online personality tests are as compelling as the Hogwarts Sorting Hat: They define you at the precise moment when the most important thing is knowing who you are. And, whether you're a Slytherin or just shy, personality quizzes sort us into social groups where we feel safe knowing that there are others just like us.