Seismic waves are waves of energy that travel through the Earth's layers, caused by the sudden release of energy in the Earth's crust due to processes like earthquakes, volcanic eruptions, or explosions. These waves propagate by traveling through the Earth in all directions from the source of the energy release. There are several types of seismic waves, including P-waves (primary waves), S-waves (secondary waves), and surface waves, each with different characteristics and speeds of propagation.
