The navigational freedom in conventional hypermedia applications leads to c
omprehension and orientation problems [Nielsen 1990]. Adaptive hypermedia a
ttempts to overcome these problems by adapting the presentation of informat
ion and the overall link structure, based on a user model. This paper intro
duces a framework for adaptive hypermedia systems (AHS). It briefly describ
es some popular methods and techniques for adaptation. Examples and evaluat
ions of existing AHS are used to illustrate the potential benefits of using
adaptation in hypermedia applications.