When the object vibrates, its pushing against the air particles around it. This causes the particles to vibrate. As these particles vibrate, they start to travel away from the source object. These particles soon transform into a longitudinal wave. The energy created from these particles goes from molecule to molecule and the compression in the longitudinal wave is the energy.
Sound waves can only travel through matter and not empty space. This means they can travel through solids, liquids, and gases, but are unable to travel through a vacuum. The speed of sound is entirely dependent on the type of medium it travels through. For example, in dry air (20 C) the speed of sound is 343 m/s but in room-temperature seawater, sound travels at 1531 m/s.