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A serious question here, and I realize that probably no one is going to have a definitive answer but I'm raising the question anyway.  This is just something which bugs me a bit. What is that apparently nudges people to take and post (often many) photos/snapshots of themselves, photos of their food, photos of their (ahem, usually mundane) everyday activities and promptly post the images for people to see on Facebook, Instagram and other online places?   Is it being narcissistic or something else?  Why do they think anyone else beyond close family and friends would care?