Hedy Lamarr was a famous movie star in the 30s, 40s and 50s. She was known for her beauty as much as her acting. But few knew that she was also a brilliant scientist. She loved inventing. Some of her inventions include a glow-in-the-dark dog collar, a redesigned traffic light, and a way to change water into soda! Her greatest invention is used by all of us now but she didn't get the credit for it. What do you think it may be?