* P-waves (Primary waves): These are compressional waves, meaning they cause particles in the rock to vibrate back and forth in the same direction that the wave is traveling. Think of it like a slinky moving forward. P-waves are the fastest type of seismic wave and can travel through both solids and liquids.
* S-waves (Secondary waves): These are shear waves, meaning they cause particles in the rock to vibrate perpendicular to the direction the wave is traveling. Think of it like a rope being shaken up and down. S-waves are slower than P-waves and can only travel through solids.
Both P-waves and S-waves provide valuable information about the Earth's interior. By studying how these waves travel through the Earth, scientists can learn about the composition, density, and temperature of different layers within the Earth.
