Visual scaffolding, a type of scaffolding provided in a visual format, is considered to have potential in web-based learning environments as it naturally includes tacit information, highlights the critical features of tasks and promotes learning through the spatial organization of tasks. However, systematic approaches to visual scaffolding design…

This article is a survey of program visualization systems intended for teaching beginners about the runtime behavior of computer programs. Our focus is on generic systems that are capable of illustrating many kinds of programs and behaviors. We inclusively describe such systems from the last three decades and review findings from their empirical…