​A simple example of such waves is compressions moving along a slinky. One can generate a longitudinal wave by pushing and pulling the slinky horizontally. Compressions are high-pressure regions where wave particles are close together. Rarefactions are low-pressure regions where particles are spread further apart.

As you can see, compressions travel from left to right, and energy is transferred in the same direction. However, not even a single particle is transported along the longitudinal wave. Instead, they all move forward and backward between compression as the wave travels through a medium.​​