An earthquake is a sudden shaking of the ground caused by the movement of tectonic plates beneath the Earth's surface. These movements can release energy that creates seismic waves, leading to the shaking we feel during an earthquake. The intensity and duration of the shaking can vary greatly, depending on the earthquake's magnitude and depth. Earthquakes can have devastating effects, including damage to buildings, infrastructure, and loss of life. They are measured using the Richter scale or the Moment Magnitude scale, which help to assess their strength. Preparedness and early warning systems are crucial in minimizing the impact of these natural events.