Jacques Cousteau was a renowned French explorer, conservationist, and filmmaker, best known for his pioneering work in marine exploration. He co-invented the Aqua-Lung, which allowed divers to explore the ocean depths more freely, and he dedicated his life to studying and protecting marine ecosystems. Through his documentaries and television series, such as The Undersea World of Jacques Cousteau, he brought the wonders of the ocean to millions, raising awareness about the importance of ocean conservation. Cousteau's legacy continues to inspire new generations to appreciate and protect our planet's oceans.