Karl Peglau was a man who designed a special type of traffic light called the "Ampelmännchen," which is a cute little figure used for pedestrian crossings in East Germany. This figure is still used today in many parts of former East Germany.
Karl Peglau made sure that the Ampelmännchen figure was very clear and easy to understand for both children and grown-ups. He wanted to make sure that people who were walking and crossing the street knew exactly when it was safe to cross.
So instead of using the usual green and red lights that you might be used to seeing on traffic lights today, Karl Peglau made the Ampelmännchen with a green figure showing people when it's ok to walk and a red figure telling people to stop and wait.
Karl Peglau is very well known in Germany for his creative and helpful design which makes crossing the street safer and easier for everyone!