Underwater volcanoes, also known as submarine volcanoes, are volcanic structures that form beneath the ocean's surface. They can erupt lava, ash, and gases, contributing to the formation of new landmasses and altering oceanic landscapes. Most underwater volcanoes are found along tectonic plate boundaries, where plates either collide or pull apart, creating conditions for volcanic activity. These volcanoes play a crucial role in the Earth's geology and ecosystem. They can create hydrothermal vents, which support unique marine life, including chemosynthetic bacteria and tube worms. Understanding underwater volcanoes helps scientists learn more about plate tectonics and the Earth's formation.