Graphical facilities are an important and extremely versatile component of the . environment.
It is possible to use the facilities to display a wide variety of statistical graphs and also to build entirely new types of graph. The graphics facilities can be used in both interactive modes, but in most cases, interactive use is more productive. Interactive use is also easy because at startup time . Once the device driver is running, . Low-level plotting functions add more information to an existing plot, such as extra points, lines and labels.