A language is a dynamic set of visual, auditory, or tactile symbols of communication and the elements used to manipulate them. Language can also refer to the use of such systems as a general phenomenon. Language is considered to be an exclusively human mode of communication; although animals make use of quite sophisticated communicative systems, none of these are known to make use of all of the properties that linguists use to define language. This book presents important research in the field from around the globe.