Orange is an open-source data visualization and analysis tool for novice and expert users. It was developed in Python and is available for Windows, Mac OS X, and Linux. Orange provides tools for data mining, machine learning, and statistical analysis through a graphical user interface and Python scripting. Some key features include visual programming, data visualization, interaction and analytics capabilities, a large toolbox of algorithms, and extensibility. Orange has been used by organizations like AstraZeneca for drug development.