Seismic waves are vibrations that travel through the Earth, typically generated by events like earthquakes or volcanic eruptions. These waves carry energy away from the source and can be detected by instruments called seismometers. There are two main types of seismic waves: P-waves, which are primary waves that move quickly and can travel through solids and liquids, and S-waves, which are secondary waves that move slower and can only travel through solids. Seismic waves help scientists understand the Earth's internal structure and the dynamics of tectonic plates. By analyzing the speed and path of these waves, researchers can infer information about the composition and state of materials deep within the Earth. This knowledge is crucial for assessing earthquake risks and improving building designs in vulnerable areas.