Amazon reported some blockbuster numbers this week, with quarterly profits of $2.5 billion — a nearly 1,200 percent increase over this time last year. When you think of Amazon, you probably think of its giant online store where you buy a year’s worth of paper towels or order groceries delivered to your house. But one of the biggest moneymakers for Amazon has nothing to do with its retail operations. It’s a segment of the business called Amazon Web Services.

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