Just like humans, dogs have vocal cords located in their larynx (voice box). When air passes over these cords, they vibrate, creating sound.
* Barking is a sharp, short sound made by quickly and repeatedly opening and closing the vocal cords. It's often used for communication, warning, or excitement.
* Growling is a deeper, rumbling sound produced by partially closing the vocal cords and forcing air through them. It's generally a threat display or warning to other animals.
While both barking and growling involve the vocal cords, the differences in sound are achieved by adjusting the tension of the vocal cords and the amount of air flowing through them.