chocolate
Smooth paste made with cocoa and sugar, extensively used in making candy and pastry and often eaten plain, as bars or squares.
dark chocolate 
Includes semisweet and bitter chocolate, which contain from 35% to 70% chocolate liquor; it is often used in cooking and is also eaten plain.
milk chocolate 
Made with chocolate liquor and cocoa butter mixed with powdered milk; it cannot be used in cooking because the milk solids it contains burn when heated.
white chocolate 
Sweet and creamy, it is made from cocoa butter, sugar and condensed or powdered milk.
cocoa 
The key ingredient in chocolate; grinding the beans of the cacao tree produces chocolate liquor, which yields cocoa butter and cocoa powder.