Wikipedia says that affiliate marketing is a web-based marketing practice in which a business rewards one or more affiliates for each visitor or customer brought about by the affiliate’s marketing efforts. It was invented in the early days of the adult pornography industry where adult sites would pay people to refer others to watch videos. It wasn’t until 1994 when the first non-adult site (CDNow) developed a BuyWeb program, which was the first click-through affiliate marketing service.

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