Volcanic rocks are formed from the solidification of molten material called magma, which erupts from a volcano. When magma reaches the Earth's surface, it is known as lava. As the lava cools and hardens, it creates various types of volcanic rocks, such as basalt and pumice. These rocks can vary in texture and color, depending on their mineral composition and the speed at which they cooled. There are two main categories of volcanic rocks: extrusive and intrusive. Extrusive rocks form when lava cools quickly on the surface, while intrusive rocks form when magma cools slowly beneath the surface. Volcanic rocks play a significant role in shaping the Earth's landscape and are important for understanding geological processes.