Visual AgenTalk: Anatomy of a Low Threshold, High Ceiling End User Programming Environment

Typical approaches to end user programming involve design trade-offs between ease of use and expressiveness End user programming environments are either easy to use and not very expressive low thresholdlow ceiling or more difficult to use but more powerful high thresholdhigh ceiling. We propose the development of end user programming environments that are both low threshold and high ceiling by combining a collection of mechanisms that address the issues of program comprehensibility, language tailorability, and interactive multimodality. In this paper, we describe the layered anatomy of a low thresholdhigh ceiling environment that is usable by both end users and language designers. We then illustrate our theory with a description of a new low thresholdhigh ceiling end user programming environment called Visual AgenTalk.