Dog barking?

Normal Sounds Dogs Make to Communicate . . .
Dogs use their voices in a variety of ways to communicate. As puppies, they make grunting noises to communicate with littermates and mother. High-pitched crying signals that they are frustrated, afraid, or hurting. Soft whining or whimpering is their way of saying they are hungry or cold. Puppies use continual yelping or high-pitched barking to get your attention at such times as when they are shut in a crate and want out. A single yelp or bark is normal if they get stepped on, stung by a bee, or startled.

As your dog gets older, he will use other forms of vocal communication:

Whining is useful in getting an owner’s attention. It is also used to show submissiveness to other dogs.

Whimpering is not often used by adult dogs unless they are abused, cold, hurt, or very frustrated or afraid.

Howling or baying is used by some breeds to communicate over long distances. Dogs that are used in hunting often bay to signal each other that they are following the scent of the prey. When not hunting, these same dogs will respond to sirens or certain music by howling or baying.

Growling is often associated with aggression, dominance, and possessiveness. Defense and warning are the correct meanings of the growling if the dog shows a stationary posture, does not wag his tail, and curls his lip. However, growling can mean the dog wants to play if it is accompanied by tail wagging, lots of movement, and even the bringing of a toy.

Barking is normal if the dog is a watch dog. This is his way of telling his owner that something is different. The bark may sound different depending upon how the dog interprets the “different-ness” – if someone he knows and likes is coming, he may have a happy bark whereas if someone he doesn’t know or doesn’t like is coming, he may have a warning bark.

Barking is also used to get attention or show excitement or signify loneliness.