Volcanic rock, also known as igneous rock, forms when molten lava cools and solidifies. This process can occur either on the Earth's surface during a volcanic eruption or beneath the surface. Common types of volcanic rock include basalt and pumice, each with distinct characteristics based on their formation and mineral content. These rocks are often lightweight and porous, especially pumice, which can float on water. Volcanic rocks play a significant role in shaping landscapes and can provide valuable insights into the Earth's geological history. They are also used in various applications, including construction and landscaping.