Using pen and paper, a person can quickly write down ideas, as well as draw rough pictures and diagrams, deferring details until later. The informal nature of pens allows people to focus on their task without having to worry about precision.
Most applications use pens only for selecting, tapping, and dragging.
These applications simply treat the pen as another pointing device, ignoring its unique affordances. Furthermore, the few compelling applications that do exist are built from scratch , despite the fact that many of them share the same kinds of functionality. This is because of the rudimentary software support for creating pen-based applications. With respect to input and output for pens, we are at a stage similar to that of windowing toolkits in the early 1980s . Many example applications and many novel techniques exist, but there are no cohesive frameworks to support the creation of effective pen-based applications.