Popcorn, also known as popping corn, is a type of corn that expands from the kernel and puffs up when heated. Popcorn is able to pop because its kernels have a hard, moisture-sealed hull and a dense, starchy interior. Pressure builds inside the kernel, and a small explosion (or "pop") is the end result. Some strains of corn are now cultivated specifically as popping corn. From Wikipedia
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