The technology behind Amazon's surveillance-heavy Go store

Back in 2015 the firm opened a physical bookshop in Seattle and it's promised to open a further 400 more in the next few years. Seattle, the home of Amazon's current headquarters, is also the testing ground for its first physical grocery store (if you discount those Whole Foods stores it purchased last year). On January 22, Amazon Go will open for business. There are some packaged sandwiches, ready-meals and booze spread across the shop's 1,800 square feet of floorspace. But unlike other stores it has no checkouts or human cashiers.