When new parents in Rio de Janeiro buy baby food in plastic containers, they are bringing home a little piece of the U.S. shale revolution.

Amazon.com Inc. is giving shoppers another reason not to visit stores. The online giant is rolling out a free service to let its Prime members try on clothes at home, its latest attempt to crack into the fashion world.

Madrid - what retail crisis? Amid a major retrenchment by American companies such as Gap Inc., J. Crew Group Inc. and Nordstrom Inc., one player continues to defy gravity: Zara. And the rapid-fire design-and-production system that has allowed the Spanish giant to outpace rivals is now giving it a powerful platform to succeed online, an outlet that has confounded its lumbering rivals.

For decades, economics textbooks argued that suddenly weaker currencies are a boon to growth, because they make a country's exports more competitive or profitable on the global stage, which in turn boosts domestic production and employment. What if that theory no longer holds?