Sound is a form of longitudinal waves.
Sound is formed by things vibrating.
The Speed of SoundEdit
The speed of sound is dependent on the material that the sound is going through. It moves faster in a solid than a liquid or a gas because the molecules are closer together, and therefore can pass on the energy quicker.
Below are a list of values for the speed of sound in various materials:
Air(at 0°C): 330 m/s
Water: 1400 m/s
Concrete: 5000 m/s
Steel: 6000 m/s