Corn syrup by John Spottiswood.

This is a thick, sweet syrup that's popular in America, but hard to find in other countries. Unlike other sweeteners, corn syrup doesn't crystallize and turn grainy when it's cold, so it's a good choice for frostings, fudge sauces, and candies. Baked goods made with corn syrup are moister and stay fresher longer than those made with sugar. There are two types: dark corn syrup is dark brown and has a slight molasses flavor, while light corn syrup is almost clear and has a more delicate flavor. The two can be used interchangeably in many recipes. Karo is a well-known brand. Store corn syrup at room temperature.