The Hypennedia '93 is the fourth in a series of Hypertext/Hypennedia conferences that have taken place in Basel, Dannstadt, and Graz. All these conferences--including the Hypennedia '93--were jointly organized by the respective Special Interest Groups of the Infonnation Technology Associations of Austria (OCG), Gennany (GI), and Switzerland (SI). The tenn hypermedia--as it is used at the present time--stands for infonnation that is organized with links that connect portions of infonnation. At the same time, hyper­ media signifies that these infonnation portions may be of an arbitrary medium type like text, graphics, image, sound, video, or executable code. We also refer to 'pure' hy­ pertext and to 'pure' multimedia as hypennedia. The former is of a uniform medium type, namely text, and the latter may be arranged in a strictly linear