A 'dark' store
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Online food shopping: What is a 'dark' supermarket?

On the High Street, the big supermarkets are diversifying - both Sainsbury's and Tesco now have more smaller sized convenience stores than larger, traditional supermarkets.

An increasing number of people are also shopping online.

Tim Muffett reports from a 'dark' store.

Go to next video: 'Supermarkets have got to adapt'