I just love listening to the sounds of birds talking to each other.  Their chirps are just great.
me too! I had parakeets and i loved to hear them talk. Bird songs are the bird sounds that are melodious to the human ear
Bird vocalization
the distincion between songs and calls is based upon compelexity and length, isn't it cool
Are they communicating with each other in any way?
yup. for example songs that are longer and more complex are usually associated with courtship and mating
I wonder how loud some of their songs can get.
i think it depends on a breed! Bird songs is best developed in the order Passeriformes
Do you know if any birds don't make noise at all?
yes, some birds are nearly voiceless. storks only make clatter sounds