Sound waves are longitudinal waves. In longitudinal waves, the particles of the medium through which the wave is traveling move parallel to the direction of the wave's energy transfer. This is in contrast to transverse waves, where the particle movement is perpendicular to the direction of the wave's energy transfer. A common example of a longitudinal wave is a sound wave, where the air particles vibrate back and forth in the same direction as the wave's propagation, creating areas of compression (high pressure) and rarefaction (low pressure) as the wave moves through the medium. read more >>

Transverse waves. Light and other types of electromagnetic radiation are transverse waves. Water waves and S waves (a type of seismic wave) are also transverse waves. In transverse waves, the vibrations are at right angles to the direction of travel.read more >>