The type of waves where the medium moves perpendicular to the direction of wave movement are called transverse waves.

Here's a breakdown:

* Transverse Waves: In these waves, the particles of the medium oscillate up and down (or side to side), perpendicular to the direction the wave travels. Think of a wave on a rope or the ripples on the surface of water.

* Longitudinal Waves: In these waves, the particles of the medium oscillate back and forth in the same direction as the wave travels. Sound waves are a good example – the air molecules compress and expand in the same direction the sound travels.

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