Longitudinal waves cause particles to vibrate parallel to the direction of wave travel while transverse waves cause particles to vibrate perpendicular to the direction of wave travel. Mechanical waves can be either longitudinal or transverse, with the key difference being the direction of particle vibration relative to the wave's direction of propagation.

1. Types of “Mechanical” Waves:
Longitudinal Waves – a wave that causes particles to vibrate in the same direction as
(parallel to) the direction that the wave is traveling
((( )))
Transverse Waves – a wave that causes particles to vibrate in a direction
perpendicular to the direction that the wave is traveling