A Longitudinal wave proceeds in the form of compression and rarefaction which is the stretched rubber band.
For a longitudinal wave at places of compression the pressure and density tends to be maximum, while at places where rarefaction takes place, the pressure and density are minimum.
Longitudinal waves are known as Compression waves.
Examples of longitudinal waves: Sound waves, tsunami waves, earthquake
P - waves, ultra sounds, vibrations in gas, and oscillations in spring, internal water waves, and waves in slink etc.
In gases only longitudinal waves propagate.