Sound is a form of vibration passing through the air or some other material. Sound travels in the form of waves but, unlike electromagnetic waves, sound waves cannot pass through a vacuum. The frequency of a sound wave controls its pitch. Long wavelengths produce deep sounds, while short wavelengths produce higher sounds. The loudness of a sound depends on the height of the sound waves, or their amplitude. The higher the amplitude, the louder the sound.
Sound vibrations are received in your ears. They are conveyed to a mechanism inside your ears that first amplifies them, and then converts the vibrations into signals that your brain interprets as sound.
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