Seismologists are experts in the study of earthquakes and the waves they produce. As a seismologist, I can explain the differences between P waves, S waves, and surface waves. P waves, also known as primary waves, are the fastest moving waves generated by an earthquake. They are compressional waves that can travel through solids, liquids, and gases, and are the first waves to be detected by a seismograph. P waves cause the ground to move back and forth in the same direction as the wave is traveling. S waves, or secondary waves, are slower than P waves and can only travel through solids. They are shear waves that move the ground perpendicular to the direction of the wave's travel. S waves are felt as a shaking motion and are the second type of body wave to be detected after P waves. Surface waves, on the other hand, propagate only at the interface between two different media, like the interface between Earth and the atmosphere (i.e., the surface of the Earth). There are two main types of surface waves: Love waves and Rayleigh waves. Love waves move the ground in a side-to-side motion, similar to a snake slithering, while Rayleigh waves cause a more rolling motion. In summary, P waves are fast compressional waves that can travel through all states of matter, S waves are slower shear waves that can only travel through solids, and surface waves are slower yet and only travel along the surface of the Earth. read more >>

On the other hand, surface waves propagate only at the interface between two different media, like the interface between Earth and atmosphere (i.e. the surface of the Earth). Body waves are of two types: Primary waves (also called P-waves, or pressure waves) and Secondary waves (S-waves, or shear waves).read more >>