Navigation in Hypertext
Backtrack function provides users a way to go backward to their last visited node. When a hypertext system does not offer backtracking the user may get stuck when reaching a node with no outgoing links. To avoid this problem almost all hypertext systems offer backtracking. In Internet Explorer, it is implemented by the Back Button. Most internet browsers provide this function. Besides, the Forward function is also provided to undo the backtracking. Howerver, there problem is that most of them not support the backtrack function according to the metaphor of Adriadne's thread. Neumueller gave the following example:
As indicated by the dotted line (Adriadne's thread), we take the path A->B->C->F, then backtrack F->C->B and proceed B->E->D. If we execute the backtrack command now, it will take us to the starting point A on the shortest way D->E->B->A and not on the actual hodological path D->E->B->C->F->C->B->A. In other words, we ''loose the memory'' of ever having been at point F because Adriadne's thread has been pulled tight by the system.
Last modified: 6 Nov 2002 by Kathy Nguyen Dang