Terminology
Americans use the terms "hot chocolate" and "hot cocoa" interchangeably. In other places, a distinction is made between "hot cocoa", made from powder made by removing most of the rich cocoa butter from the ground cacao beans, and "hot chocolate", made directly from bar chocolate, which already contains cocoa, sugar, and cocoa butter. Thus, the major difference between the two is the cocoa butter, the absence of which makes hot cocoa significantly lower in fat than hot chocolate while still preserving all the antioxidants found in chocolate.
Hot chocolate can be made with dark, semisweet, or bittersweet chocolate chopped into small pieces and stirred into milk with the addition of sugar. American instant hot cocoa powder often includes powdered milk or other dairy ingredients so it can be made without using milk. In the United Kingdom, "hot chocolate" is a sweet chocolate drink made with hot milk or water, and powder containing chocolate, sugar, and powdered milk. "Cocoa" usually refers to a similar drink made with just hot milk and cocoa powder, then sweetened to taste with sugar.
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