Response: Each and every visualization in ggplot2 package in R comprises of the following key aspects – Data – The raw material of your visualization Layers – What you can see or visualize on plots (i.e. lines, points, maps etc.) Scales – Maps the data to graphical output Coordinates – This is from the visualization perspective (i.e. grids, tables etc.) Faceting – Provides “visual drill-down” into the data Themes – Controls the details of the display (i.e. fonts, size, colour etc.)