Shoppers Manuel Orellano, middle, with his daughter Marcela, left, and her son Manuel, 6, shop for children's clothing at JCPenney at Glendale Galleria shopping mall in Glendale, Calif, on Friday. Damian Dovarganes/AP hide caption

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Retailers' Black Friday ads and other parts of the holiday season are designed to tap into a very ancient part of our brains. Paul J. Richards/AFP/Getty Images hide caption

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NPR producer Olly Dearden is a fan of most classic Thanksgiving dishes, but calls sweet potatoes topped with marshmallows a "culinary abomination." Stephen Little/Flickr hide caption

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Festivalgoers browse for books during the Miami Book Fair International. PBS will provide live coverage of the fair's events over the course of three days this year. Roberto Schmidt/AFP/Getty Images hide caption

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The scene at the registers in a Braintree, Mass., Target store on Black Friday. Allison Joyce/Getty Images hide caption

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Buy more, or buy less, this holiday season; the choice is yours. Matt Cardy/Getty Images hide caption

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Shoppers wait to get inside of a Best Buy store on Nov. 25 in Naples, Fla. Spencer Platt/Getty Images hide caption

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