UUelcome to UUhistle.org

UUhistle (pronounced "whistle") is a tool for visually and interactively exploring the execution-time behavior of computer programs. Through UUhistle's graphics, novice programmers can improve their code-tracing skills and understanding of programming concepts and programming-language constructs.

Unlike a regular debugger, UUhistle displays challenging aspects of program execution such as parameter passing and object references in a detailed, beginner-friendly manner.

Unlike a typical program animation system, UUhistle supports an unusually interactive learning activity in which the student takes the role of the computer to execute programs.

Here's a screenshot of UUhistle in action:

screenshot of UUhistle
(Click for a larger image)

There are three main ways of using UUhistle:

Read more about UUhistle or try it out right now.

website maintained by Juha Sorva