introductory
     adj 1: serving to open or begin; "began the slide show with some
            introductory remarks"
     2: serving as a base or starting point; "a basic course in
        Russian"; "basic training for raw recruits"; "a set of
        basic tools"; "an introductory art course" [syn: {basic}]
     3: serving as an introduction or preface [syn: {prefatorial}, {prefatory}]
Source: WordNet® 2.0