To my surprise, a lot of people don't know there exist things called debuggers. Debuggers are tools that let you step through code, see variables, set break points. Debuggers are common for compiled languages, less common for scripting languages. For example, you can debug Java code from most IDEs, or C++/C# code from Xcode or Visual Studio.<p><a href="http://en.wikipedia.org/wiki/Debugger" rel="nofollow">http://en.wikipedia.org/wiki/Debugger</a>
hi (i'm the guy who created this app) ... if anyone finds security vulnerabilities, please email me (and don't rm -rf my account hehe). i put this up a few months ago as a small hack to teach people Python, so it wasn't meant to be pounded by 1337 h4x0rz. thanks!
One of my goals is to use this app as the foundation for some free online introductory programming tutorials. Unfortunately, I don't have much free time right now to pursue this goal; but if you're interested in getting involved, please email me!
The idea of a code stepper is pretty cool. Two other projects that come to mind after seeing this: <a href="http://jonnytran.com/machina/" rel="nofollow">http://jonnytran.com/machina/</a> and the Macro Stepper in Racket: <a href="http://docs.racket-lang.org/macro-debugger/index.html" rel="nofollow">http://docs.racket-lang.org/macro-debugger/index.html</a>