For anyone who has ever waited in a long line at the grocery story, Amazon hopes it has a solution. In December, Amazon launched its new Amazon Go grocery store in Seattle. Amazon Go is not a typical supermarket: it has no check-out lanes and no cashiers. Instead, shoppers walk in, select items, and walk out.How does this work? Customers simply scan their Amazon app loaded cell phones upon entry into the store, and Amazon’s “Just Walk Out” technology then tracks each shopper’s virtual cart, keeping track of items customers take off of or return to shelves. Once done shopping, customers simply leave the store, which then charges customers’ Amazon.com accounts automatically.

How does this work? Customers simply scan their Amazon app loaded cell phones upon entry into the store, and Amazon’s “Just Walk Out” technology then tracks each shopper’s virtual cart, keeping track of items customers take off of or return to shelves. Once done shopping, customers simply leave the store, which then charges customers’ Amazon.com accounts automatically.

Amazon has not revealed much about its new technology beyond explaining that “Just Walk Out” uses “the same types of technologies used in self-driving cars: computer vision, sensor fusion, and deep learning.” The Amazon Go store might be using increasingly-popular retail technologies, such as radio frequency identification (“RFID”) or mobile location analytics (“MLA”), on which we previously reported RFID uses small, digital tags to track items, and might be how the Amazon Go store keeps track of items in shoppers’ virtual carts. MLA technology uses a mobile device’s unique MAC address, which broadcasts the device’s location; retailers can install sensors in stores to track customers’ in-store movements via their mobile devices. The Amazon Go concept likely uses these, or similar, technologies to track both customer movements and inventory to ensure accuracy.

For a retail giant who revolutionized online shopping, Amazon’s decision to build another brick-and-mortar store might confuse some. Online shopping gives customers convenience and flexibility that often cannot be recreated in stores, all without ever leaving their homes. Amazon’s Prime service introduced fast shipping speeds, often no more than two days, which further incentivized online shopping. But, despite Amazon’s attempts with its grocery delivery service, Amazon Fresh, most consumers still prefer to pick out groceries in person. If Amazon Go successfully makes grocery store visits faster and easier, shoppers will likely respond enthusiastically.

At 1,800 square feet, the Amazon Go store is relatively small compared to supermarkets, but it will sell most grocery staples like bread, produce, and milk; it will also offer a wide variety of ready-made food, catering to its busy shoppers. The Seattle store is currently in Beta and open only to Amazon employees. According to Amazon, the store will open to the general public in early 2017. Depending on the initial store’s performance, Amazon may build as many as 2,000 Amazon Go grocery stores across the United States in the next decade. If shoppers’ desire for convenience makes Amazon Go a success, a few years from now, check-out lines might be a thing of the past.