SEE PHOTOS | Inside Amazon Go: No cashiers, no registers. no cash

The online retailer opened its 'future of store shopping' concept to the public yesterday in Seattle with its first Amazon Go store, which lets shoppers take milk, potato chips or ready-to-eat salads off its shelves and just walk out. The store is yet another sign that Amazon is serious about expanding its physical presence.

The online retailer opened its 'future of store shopping' concept to the public yesterday in Seattle with its first Amazon Go store, which lets shoppers take milk, potato chips or ready-to-eat salads off its shelves and just walk out. The store allows shoppers to scan their smartphone with the Amazon Go app at a turnstile, pick out the items they want and leave. It can tell what people have purchased and automatically charges their Amazon account| AP Photo 

More than a year after it introduced the concept, Amazon opened its artificial intelligence-powered Amazon Go store in downtown Seattle. Not everyone can shop at the store: People must have a smartphone and a debit or credit card they can link to be charged | | AP Photo

Sensors and cameras, part of a system used to tell what people have purchased, are attached overhead as shoppers walk below, in an Amazon Go store. There's little sign of the technology visible to customers, except for black boxes, cameras and a few tiny flashing green lights in the darkened, open ceiling above. | AP Photo

Amazon.com Inc. said it uses computer vision, machine learning algorithms and sensors to figure out what people are grabbing off its store shelves. | AP Photo

One shopper, Paul Fan, tested the technology by turning off his phone and taking items and putting them in incorrect spots. The app was still able to tally up his items correctly. | AP Photo

Amazon said families can shop together with just one phone scanning everyone in. Anything they grab from the shelf will also be added to the tab of the person who signed them in. But don't help out strangers: Amazon warns that grabbing an item from the shelf for someone else means you'll be charged for it. | AP Photo

'It's such a weird experience, because you feel like you're stealing when you go out the door,' Lisa Doyle told AP, who visited the shop yesterday. | AP Photo

At 1,800 square feet, Amazon Go resembles a convenience store, except for a kitchen visible from the street where sandwiches and ready-to-cook meal kits are prepared. A small section features products from the Whole Foods 365 brand. | AP Photo