Facebook and Twitter head into retail terrain

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Facebook and Twitter face different growth scenarios, but both are now focusing their gaze on the same market: Retail.

There's a logical reason for the shift. The social networking sites are testing out "buy" buttons in an effort to tap into the $304 billion that eMarketer estimates will be spent on e-commerce this year. U.S retailers will spend $11.2 billion on digital ads, and 37 percent of those digital ad budgets will be focused on mobile, an area of strength for both Facebook and Twitter.