By Alex Fitzpatrick and Arpita Aneja
During the recent attacks in Paris, Facebook activated a feature that let people in the city let their friends and family know they were safe. Called “Safety Check,” the feature grew out of a project created after the devastating earthquake and tsunami that struck Japan back in 2011.
For everything you need to know about Facebook’s Safety Check, watch the Tech Time video above.
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Write to Arpita Aneja at arpita.aneja@time.com