In 1997, Python bindings were developed for ML*, which together with emerging Python modules formed a joint framework called Orange.
During the following years most major algorithms for data mining and machine learning have been developed either in C++ (Orange's core) or in Python modules.
In 2002, first prototypes to create a flexible graphical user interface were designed, using Pmw Python megawidgets.
In 2003, graphical user interface was redesigned and re-developed for Qt framework using PyQt Python bindings. The visual programming framework was defined, and development of widgets (graphical components of data analysis pipeline) has begun.