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\subsection{Visualization}  Edward Tufte’s work in visualization laid down the basic principles of effective visualization as foundation to visual designs \cite{Tufte_1992} \cite{1988}\cite{Tufte_1998}.The visuals rules were summarized and presented in mid 90s showed three effective visual representation rules i.e. (i) Natural encoding of information; (ii) Task specific graphics; (iii) No gratuitous graphics \cite{Mahadev_1993}. T. Norrentranders research describes the importance of visualization where he expressed the comparison of human senses in a visualization shown in figure 1 \cite{Mahadev_1993}  Human can decipher color coding much faster than reading and analyzing data. The visualization technique used in any system should be cognitive i.e., they should be recognized and understood by the operators easily. Visualization principles applied to power system structure create beautiful and more meaningful visualization compared to one-line diagram.  https://www.authorea.com/users/18452/articles/20728/master/file/figures/Capture/Capture.PNG  \subsection{Power System Visualization}  Power system visualization is one of the hot topics of research because of vulnerability of power system to blackouts, earthquakes and other catastrophic events including instrument failures which can lead to unexpected changes which are not expected by power system operators. Earlier, One-Line diagram was the only centric method which was researched for representation of power system networks. Dr. Thomas Overbye and his collaborators making significant contribution for improvement in one line diagram[6]. The contour plot is further enhanced to visualize variety of data, such as power flow in transmission line [7], locations marginal prices [8], contingency analysis [9], third dimension to visualize various data [10]. This research in visualization revolutionized the one-line diagram with flow animation, pie charts, arrows for flows, colors as shown in figure 2. In figure 2, above visualization of IEEE 39 bus system provides information of power flow with green and red arrows as per the status of power flow with blue pie charts and overloads at which can be seen in red is shown which is indeed a great work but it fails to take advantage of the analytical strengths naturally gained by the visualization itself of connected network [11].   https://www.authorea.com/users/18452/articles/20728/master/file/figures/118%20case/118%20case.PNG