In these years computer scientists have devoted a lot of efforts to the development of declarative languages which constitute an essential part in the field of artificial intelligence However, only a few planners and physical designers recognize the potential usages of declarative languages From the viewpoint of users, declarative languages provide an environment such that users can concentrate on the problems which they are interested without worrying about the details of programming design This article introduces some declarative languages, such as many sorted algebraic language, formal language, logic programming language (Prolog), and constraint logic programming language, by which the spatial objects can be described.