For over a decade, Amazon had subsidized the cost of a Kindle with a program called Special Offers. This put advertisements on the home screen and the lock screen, it costs around $20 to remove it. Amazon is undergoing a rebranding effort of Special Offers and is now calling it Ad-Supported and if you want the adfree model they are calling it Without Ads.
Currently the new Ad-Supported and Without Ads monikers are live in the United States. Only new models such as the Kindle Basic, Kindle Paperwhite and Kindle Oasis are showcasing the new text, refurbished units and Fire tablets continue to show the old text.
Amazon will likely change the design language from Special Offers to Ad-Supported across their entire line of tablets and refurbished e-readers sometime in the next few weeks and likely expand it into other markets sometime soon.
I think this is a good move on Amazon’s part because Special Offers does not really mean anything and would likely just confuse new users. Ad-Supported and Ad-Free basically tells people more clearly on what they are getting.