It is always a good idea to include a plot as part of your statistical analysis. Plots allow for a more intuitive grasp of the data, making them ideal for presenting your results to those without statistical expertise. They also make it easier to spot features of the data such as outliers or a bimodal distribution, which you may overlook when using other methods.
One of the strong points of R is that it makes it easy to produce excellent quality, fully customizable plots and statistical graphics. This chapter explains how to create the most popular types, which are: