wxWindows is an open source cross-platform GUI framework for C++, Python and over 9 other languages that enable a program to compile and run on several computer platforms with only minimal code changes. wxWindows is set apart from other such kits not only by its extensive coverage of functionality (graphics, network, etc.), but also by its ability to use "native" gadgets and, if needed, emulate foreign ones, giving the resulting program the look and feel of the platform it runs on.
wxWindows was started in 1992. It covers systems like Windows, Apple Macintosh, Linux/Unix (for X11, Motif, and GTK), OpenVMS, and OS/2. An embedded version is being worked on.