Getty Images Pizza is super cheap at Costco.

Pizza has reached a new pinnacle. It’s available in more places, and in weirder and more wonderful varieties, than ever before. And we’re scarfing it down: The research firm Technomic estimates that Americans eat 350 slices per second, and more than 4 in 10 of us now munch on pizza at least once a week. Read on for a brief look back at some of the big innovations that have helped pizza become fully ingrained in modern American dining culture.

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