Description:

DrScheme is an interactive, integrated, graphical programming
environment for the MzScheme programming language, and the MrEd
windowing toolbox.

DrScheme provides source highlighting for syntax and run-time errors,
support for multiple language levels, an algebraic stepper, objects,
modules, a GUI library, TCP/IP, and much more. It includes an
extensive, hyper-linked help system called Help Desk, available from
the Help menu.

You can enhance DrScheme with many add-ons, including MrFlow, a static
debugger.

MzScheme is R5RS-compliant, including the full numerical tower. It
also provides threads (on all platforms), exceptions, modules,
class-based objects, regular-expression matching, TCP/IP, and more.

MrEd provides a windowing toolbox for creating windows and menus; a
drawing toolbox for drawing to windows, bitmaps, and printer devices;
and an editor toolbox for creating multimedia editors.