In which medium, longitudinal waves can be produced?

Longitudinal waves can be produced in any medium where particles are able to oscillate or vibrate parallel to the direction of wave propagation. This includes solids, liquids, and gases. Examples of longitudinal waves include sound waves traveling through air, seismic waves traveling through the Earth's crust, and compression waves in fluids like water. In these mediums, the particles oscillate back and forth in the same direction that the wave is moving.