Over the last few decades, engineers have developed many underwater robots capable of meeting the challenges that the deep sea imposes upon explorers. They allow us to dive to depths where utter darkness, crushing pressures, and extreme cold temperatures prevent humans from going. Underwater robots, such as remotely operated vehicles (ROVs) and autonomous underwater vehicles (AUVs), are essential tools for ocean exploration. These robots explore areas of the ocean that are too dangerous or too difficult for humans to go. Underwater robots come in various shapes and sizes and can be outfitted with numerous sensors and tools to collect data from deep-sea environments. Learn about the underwater robots used to explore the ocean and use the engineering design process to develop your own tools for underwater exploration.