In geography, volcanoes are formed when magma from inside the Earth's mantle rises to the surface. This usually occurs at tectonic plate boundaries, where the Earth's crust is weakest. The magma can erupt as lava, ash, and gases, causing volcanic eruptions. There are different types of volcanoes, including shield volcanoes, cinder cone volcanoes, and stratovolcanoes. Shield volcanoes have broad, gently sloping sides and are formed by lava flows. Cinder cone volcanoes are made up of loose, rock fragments called cinders, while stratovolcanoes are tall, steep-sided volcanoes made up of layers of ash, lava, and rocks. Volcanic eruptions can have both positive and negative impacts on the environment. While eruptions can create new land and fertile soil, they can also cause destruction through the release of ash, gas, and lava. People living near volcanoes need to be prepared for potential hazards such as ash clouds, lahars, and pyroclastic flows. Understanding how volcanoes form and the potential risks associated with them is crucial in geography. By studying volcanic activity, geographers can better predict eruptions and mitigate their impact on nearby communities.