Seismic energy, S and P waves

Seismic energy or earthquake energy creates two types of waves. The first kind created by the earthquake are known as compressional waves, or p (primary) waves. These waves move back and forth parallel to the direction of the wave itself. These types of waves can move through solids, liquids and gases; and they also travel through the entire earth, including the core. The second waves created are shear (s) waves. S waves travel in "waves" when they're moving. S waves can only travel through solids, and they are much slower then p waves. Unlike p waves, s waves do not travel through the core, rather they are deflected off around the earth when they reach the outer core. The actions of S and P waves contribute to the theory that earth's outer core is indeed made of liquid iron.