Baking powder is a chemical leavening agent. That’s a fancy way of saying it’s a tiny, powdery factory that creates bubbles of carbon dioxide gas.
When you mix it with water or heat, it goes “POOF!” and makes your cakes, muffins, and pancakes rise up like they’re hitting the gym. It usually contains baking soda (a base), cream of tartar (an acid), and a bit of cornstarch—just to keep it dry so it doesn’t blow up in the can.
So, ironically, some baking powder contains cornstarch as an ingredient. But that’s like saying a car contains tires, so a tire is a car. Not quite, buddy.