The seismic waves that travel through earth’s interior are waves.

The seismic waves that travel through Earth’s interior are known as the P waves and the S waves, these seismic waves have differences, first the P waves compress and enlarge the foundations(rocks) as they move through it, while the S waves, shakes the particles of their medium up and down and side-by-side. P waves can travel through solid granite, magma, water or even air, while S waves can only travel through solids, they are unable to travel through fluids. The P waves are the fastest of all known seismic waves, it is the first seismic wave to register on the seismograph, while the S wave is the second one.