The common name for the device that measures earthquakes is a seismometer, or seismograph. This instrument detects and records the motion of the ground caused by seismic waves resulting from earthquakes, volcanic activity, or explosions. Seismometers consist of a mass suspended from a fixed base; when seismic waves travel through the Earth, the mass remains stationary while the base moves, allowing for the measurement of vibrations. The data collected helps scientists analyze various seismic events, providing valuable information for understanding earthquakes, assessing risks, and improving building safety standards in seismically active regions.