Sound waves are a type of energy that travels through the air, or any other medium, like water or metal. They are created by vibrations, which are produced when something vibrates. The vibrating object causes the air around it to vibrate too. Sound waves are usually described by how fast they vibrate, or their frequency. The faster the vibration, the higher the pitch of the sound. The slower the vibration, the lower the pitch. They can solve problems in physics. For example, equations can be used to calculate the speed of sound waves. Answers to questions about waves and sound can also be found by using sound waves.