A seismologist is a scientist who studies earthquakes and the movement of the Earth's crust. They analyze seismic waves, which are vibrations that travel through the Earth, to understand how and why earthquakes occur. By examining these waves, seismologists can determine the location, depth, and magnitude of an earthquake. Seismologists use various tools and instruments, such as seismographs, to record and measure seismic activity. Their research helps improve earthquake prediction and safety measures, contributing to the fields of geology and earth science. They often work with geologists and engineers to develop better building designs that can withstand seismic events.