The natural phenomenon characterized by a sudden release of energy in the Earth's crust is known as an earthquake. This release of energy can occur due to tectonic plate movements, volcanic activity, or human-induced factors like mining. Earthquakes result in seismic waves that travel through the Earth, potentially causing ground shaking, surface rupture, and secondary effects like tsunamis or landslides. Their magnitude is measured using the Richter scale or moment magnitude scale, and they can have devastating impacts on communities, infrastructure, and ecosystems, underlining the importance of understanding seismic activity for disaster preparedness.