Seems like this depends on who you ask? (https://techcrunch.com/2016/07/02/andy-jassys-brief-history-of-the-genesis-of-aws/ https://techcrunch.com/2016/07/02/an

Seems like this depends on who you ask? (https://techcrunch.com/2016/07/02/andy-jassys-brief-history-of-the-genesis-of-aws/ https://techcrunch.com/2016/07/02/andy-jassys-brief-history-...) > "It began way back in the 2000 timeframe when the company wanted to launch an e-commerce service called Merchant.com to help third-party merchants like Target or Marks & Spencer build online shopping sites on top of Amazon’s e-commerce engine...At that point, the company took its first step toward building the AWS business by untangling that mess into a set of well-documented APIs." > "The internal teams at Amazon required a set of common infrastructure services everyone could access without reinventing the wheel every time, and that’s precisely what Amazon set out to build — and that’s when they began to realize they might have something bigger." > As the team worked, Jassy recalled, they realized they had also become quite good at running infrastructure services like compute, storage and database (due to those previously articulated internal requirements). What’s more, they had become highly skilled at running reliable, scalable, cost-effective data centers out of need. As a low-margin business like Amazon, they had to be as lean and efficient as possible. > "It was at that point, without even fully articulating it, that they started to formulate the idea of what AWS could be, and they began to wonder if they had an additional business providing infrastructure services to developers." From The Everything Store: >"Groups within Amazon were told to use AWS while the services were still immature, a demand that led to another round of consternation among its engineers." (Page 221) I guess we could say that AWS's first customer was not necessarily Amazon, but the team and infrastructure predated AWS, and AWS was used by Amazon internally.