Here's a bit of history that most people do not know:

Lamarr was a glamorous movie star by day, but she was also a gifted, self-trained inventor who developed a technology to help sink Nazi U-boats.

In the 1940s, few Hollywood actresses were more famous and more famously beautiful than Hedy Lamarr. Yet despite starring in dozens of films and gracing the cover of every Hollywood celebrity magazine, few people knew Hedy was also a gifted inventor. In fact, one of the technologies she co-invented laid a key foundation for future communication systems, including GPS, Bluetooth and WiFi.

“Hedy always felt that people didn't appreciate her for her intelligence—that her beauty got in the way,” says Richard Rhodes, a Pulitzer Prize-winning historian who wrote a biography about Hedy.  

After working 12- or 15-hour days at MGM Studios, Hedy would often skip the Hollywood parties or carousing with one of her many suitors and instead sit down at her “inventing table.”

While not a trained engineer or mathematician, Hedy Lamarr was an ingenious problem-solver. Most of her inventions were practical solutions to everyday problems, like a tissue box attachment for depositing used tissues or a glow-in-the-dark dog collar.

It was during World War II, that she developed “frequency hopping,” an invention that’s now recognized as a fundamental technology for secure communications. She didn’t receive credit for the innovation until very late in life.

You can read more in an article by Dave Roos published in the History Channel's web site at: https://www.history.com/news/hedy-lamarr-inventor-frequency-hopping-wifi