Direct manipulation: A step beyond programming languages (abstract only)

Direct manipulation is a style of interaction which has been used by implementers of widely varying systems. Direct manipulation permits novice users access to powerful facilities without the burden of learning to use a complex syntax and lengthy list of commands. Display editors use direct manipulation more than line editors. Form-fill-in is more direct than tag fields and delimiters. Spatial data management is more direct than query-by-example, which is more direct than SEQUEL. Computer arcade games and Visicalc are further examples.Direct manipulation involves three interrelated techniques:1. Provide a physically direct way of moving a cursor or manipulating the objects of interest.2. Present a concrete visual representation of the objects of interest and immediately change the view to reflect operations.3. Avoid using a command language and depend? on operations applied to the cognitive model which is shown on the display.