The debut Kindle Singles Interview features Shimon Peres, the 89-year-old President of Israel. The interview was conducted by David Samuels, in association with Tablet Magazine. That interview, The Optimist, costs $.99 and like most Kindle Singles it is exclusively available via the Kindle Store.
Kindle Singles is a special section of the Kindle Store which Amazon launched in early 2011. In its early days it was a stealth publishing imprint (as I would call it) which focused on "compelling ideas expressed at their natural length", though that may no longer be the case now that a quarter of the Kindle Single Store is now fiction.
In late 2012 Amazon expanded the Kindle Single Store to the UK and earlier this month Amazon expanded a second time, launching a new Kindle Singles Store in Germany. Amazon currently offers 400 Kindle Singles, all priced between $.99 and $2.99.