The title "101 Graphical Techniques", itself indicates the very purpose of the book. Data visualization or graphical representation of Statistical data is now an emerging subfield of Statistics. Though various graphical techniques existed in statist!cal literature but some very common graphical techniques are found to replicate themselves in almost all books and journals. But with the advances in the field of technology the use of graphics has increased many times. Today, graphical methods play an important role in all aspects of statistical investigation-it begins with explanatory plots, supports various stages of analysis and helps in the final communication and display of results. These days we see extensive use of graphics in print media, television news, sports coverage, advertisement etc. and this gives us an idea about the development of statistical graphics. Most of the recent versions of statistical software are now producing high-resolution selfexplanatory graphics and is adding number of more graphs in every recent version of their product. However, the software packages do not provide sufficient text to support the purpose and interpretation of the relatively less common graphics and this in turn restrict their use. Social scientists can now get their data analyzed by using graphical tools that are handy and easier compared to other statistical methods.