The meaning of a string in some languaGE, as opposed to syntax which describes how symbols may be combined independent of their meaning. The semantics of a programming languaGE is a function from programs to answers. A program is a closed term and, in practical languaGEs, an answer is a member of the syntactic category of values. The two main kinds are {denotational semantics} and {operational semantics}. (1995-06-21)