<p>Fig. 2.&nbsp;When energy in a wave passes through the water, water molecules move in a circular motion. Here, a small floating object (yellow circle) returns to its original location due to the orbital motion of waves in deep water.</p>

Fig. 2. When energy in a wave passes through the water, water molecules move in a circular motion. Here, a small floating object (yellow circle) returns to its original location due to the orbital motion of waves in deep water.

Image by Byron Inouye from Exploring Our Fluid Earth