This report describes the 'gggrid' package, which provides
a convenient interface for making use of raw 'grid' functions
in combination with 'ggplot2'.
The 'gggrid' package provides two functions,
grid_panel() and grid_group(),
both of which create a new layer in a 'ggplot2' plot.
The first argument to both functions is a 'grid' grob or a function that
generates a grob and that grob is added to the plot region
of the 'ggplot2' plot.