Pushing back: evaluating a new behaviour for the back and forward buttons in web browsers

The Back button on web browsers is one of the world's most heavily used user interface components, yet its behaviour is commonly misunderstood. This paper describes the evaluation of a "temporal" alternative to the normal "stack-based" behaviour of Back and Forward. The main difference of the temporal scheme is that it maintains a complete list of previously visited pages. The evaluation compares the efficiency of the stack and temporal schemes in an "out of the box" scenario in which participants were asked to use a "new" version of a commercial browser without any explanation of the presence or absence of new features. This scenario allows us to predict the likely usability impact if commercial browsers were released supporting the temporal scheme. The results showed that the relative efficiency of the two schemes differed across different types of navigational task. In particular, the temporal system poorly supported backtracking to parent pages, but performed better for more distant navigation tasks. The temporal scheme also caused extreme usage patterns, with the subjects either solving tasks very efficiently or very inefficiently, depending on whether they used the Back menu. This observation indicates that adaptations of the temporal system that improve the effectiveness of the Back menu may enhance web navigation.