Within the world sound is used for a large amount of reasons. The versatility of sound makes it an extremely effective form of communication. Unlike light sound can be heard the same in day (where light is present) or at night (where minimal light is present). This make sound a consistent and convenient form of communication. Sound can also travel through solid, liquids and gases, allowing for it to be used almost anywhere. This is effective as it means the receiver does not have to visually see the sender in order to hear the sound. Sounds can be varied in pitch and loudness which can create communication for different information. Sounds can travel over long distances and can be heard in all directions of the sender. It can alert you to stimuli/dangers and produce warnings.
For these reasons sound can be considered a very versatile form of communication and is very effective.

Aubusson, Eileen Kennedy Peter. Biology in Context: the Spectrum of Life. Victoria : Oxford Uni. Press., 2001. Print.
"HSC Online." NSW HSC Online. N.p., n.d. Web. 25 June 2010. <http://www.hsc.csu.edu.au/biology/options/communication/2952/CommPart4.html#1>.