A family of programs has been developed to allow graphical input through continuous digitizing. Drawing data, sampled at a high and constant rate, is compressed and mapped into lines and splines, in two and three dimensions. This is achieved by inferring a particular user's intentions from measures of speed and pressure.Recent experiments have shown that even the most basic inference making cannot rely solely upon knowledge of the user's drawing style, but needs additional knowledge of the subject being drawn, the protocols of its domain, and the stage of development of the user's design. This requirement implies a higher level of machine intelligence than currently exists. An alternate approach is to increase the user's involvement in the recognition process.Contrary to previous efforts to move from sketch to mechanical drawing without human intervention, this paper reports on an interactive system for graphical input in which the user overtly partakes in training the machine and massaging the data at all levels of interpretation. The initial routines for data compression employ parallel functions for extracting such features as bentness, straightness, and endness. These are planned for implementation in microprocessors.Results offer a system for rapid (and enjoyable) graphical input with real-time interpretation, the beginnings of an intelligent tablet.