If the motion of particles is perpendicular to the the direction of propogation of wave, these waves are called Transverse waves. If the motion of the particles is parallel to the direction of propogation of wave, its called the Longitudinal wave.
Simplest examples:
Waves on a rope: Transverse
Sound Waves: Longitudinal
Light is a transverse wave, the E and B fields change perpendicular to
the motion of wave...
