This document provides an overview of data mining concepts and techniques discussed in Chapter 2 of the textbook "Data Mining: Concepts and Techniques". It defines key terms like data objects, attributes, attribute types, statistical descriptions of data, and different methods of data visualization. Various techniques are described for understanding the characteristics of data sets through statistical measures, histograms, quantile plots, scatter plots and other approaches. Different styles of data visualization like pixel plots, geometric projections, icons and hierarchies are also summarized.