LONGITUDINAL WAVES
The waves in which the particles of a medium vibrate in the direction of propagation of wave are called a longitudinal wave.
These waves propagate in the form of compressions and rarefactions.
Example: Sound waves in air.
TRANSVERSE WAVES
The waves in which the particles particles of a medium vibrate in the direction perpendicular to the direction of propagation of waves are called transverse waves.
These waves propagate in the form of Crests and troughs
Example: water ripples