This document provides an overview of data mining and the Orange software tool for data mining. It defines data mining as the process of analyzing data from different perspectives to summarize it into useful information. It then discusses major data mining tasks like classification, clustering, deviation detection, and forecasting. It also introduces the concepts of data warehouses and decision trees. The document proceeds to describe Orange, an open-source software for visual data mining and analytics. Orange contains various widgets that can be used for data preprocessing, visualization, and machine learning algorithms. Finally, the document demonstrates some Orange widgets and provides references for further information.