For Britain's supermarket chains, it's no longer just a case of selling food, it's about how you can do it better. Tesco has long thought about how technology can give it an edge over its rivals, but it's now experimenting with robotics, wearables and cognitive computing in an attempt to secure future success. That's according to Mike McNamara, Tesco's chief information officer, who revealed that the company has become the latest in a long line of retailers to leverage IBM's Watson supercomputer to explore new ideas using old data. Tesco's Labs division, the team behind its Google Glass app and other tech trials, fed Watson "thousands" of recipes and ingredients and asked it to come up with some unique meal ideas. The supermarket is already trialling smartwatches in a bid to better manage stock, but it looks increasingly likely that machines will take over such jobs in the future. McNamara believes robots that can gauge depth and height could free up time for stockroom associates, but that also brings another danger -- the risk that they'd replace workers completely.