Dogs bark for many different reasons and it is one very important way they communicate with other dogs, animals and people. Although it may seem random at times, they are usually trying to tell you something. Barking is a way for them to express their emotions such as loneliness, fear, suspicion, stress, and pleasure. Next time the dog barks, try to tune in to what they are saying by listening to the different pitches of the bark.You may be surprised what you learn.
As @swalts77 pointed out, dogs bark for many different reasons.Some common reasons are: * To warn or alert * Anxiety * Playfulness/Excitement * To seek attention * In response to other dogs * Because they're bored :)