Lava flows are streams of molten rock that emerge from a volcano during an eruption. When magma from beneath the Earth's surface reaches the surface, it becomes lava. As it flows, it can create various landforms, depending on its temperature, composition, and the terrain it travels over. The speed and distance of lava flows can vary significantly. Some flows move slowly, allowing time for people and animals to evacuate, while others can travel rapidly, destroying everything in their path. The solidified lava can form new geological features, contributing to the landscape of the Earth over time.