Embedded menus, as opposed to explicit menus, allow the user to select a word or item embedded within the text of a node and can be selected using a touch screen, cursor keys or mouse pointer. In The Interactive Electronic Encyclopedia System (TIES), selectable items are highlighted directly in the text, a method now called touchtext [Koved & Shneiderman, 1986]. The embedded menus in TIES (now called HyperTIES ) can be traversed using cursor keys and can be selected either by clicking or by a keystroke; a new node or piece of information will be retrieved. At every node in the network, the user can request a return to a previous article using other navigation mechanisms. An extension of the embedded menus approach can be found in MIT's Spatial Data Management System (SDMS) where users can select a graphical area (such as a territory in a map) and retrieve a more detailed map from the database. The user can undo the effects of the selection process by returning to less detailed maps.
Embedded menus are a better way of indexing for hypertext systems since they emphasize the understanding of concepts. They highlight semantic relationships rather than physical relationships. They provide meaningful task domain terms (as opposed to computer domain terms) and concepts, thereby reducing disorientation [Marchionini & Shneiderman, 1988]. Embedded menus reduce the "loss of context" feeling by being part of the information being displayed. They provide information hiding (layers below are shown only when requested). The extent of "embeddedness" can be varied depending on the skill level of the user. They are suitable for learning-by-browsing systems as in museums. Further research is required regarding the negative aspects of using highlighted embedded menus. It is possible that they may cause disruption, reducing speed and comprehension.