Maps or graphical browsers of structural knowledge allow the user of a hypertext system to navigate from node to node through the structure as they portray the links between concepts spatially. This study examined the results of using two different graphical browsers that provide different amounts of information about the structure of the knowledge. The use of graphical browsers was compared with that of hotwords embedded in the instructional text itself but having no explicit structure. Subjects were 113 undergraduates for whom verbal Scholastic Aptitude Test scores served as a measure of verbal ability. Treatment effect was assessed through posttests, and student paths were recorded for each treatment. It was not evident from the results that all learners internalized the structural knowledge provided by the graphical browsers. Those with high prior knowledge showed a greater increase in structural knowledge. Use of hotwords resulted in lower achievement, and verbal ability was not a factor on most variables. Users of hypertext appear to require extended experience to become comfortable and proficient. Twelve tables present study findings. (Contains 68 references.) (SLD)