Choose an Appropriate Graphics File Format
If you don’t know which graphics file format to use for your plots,
this link can help you narrow down your options. Please make sure to
Determine Available Graphing Functions first.
.png and .gif
Graphics shared over the web do best in png when they contain regions of monotones with hard edges (e.g., typical line graphs). The .gif format also works well in such scenarios, but it is not supported in the default R installation because of patent issues. The GDD package allows you to create gifs in R.
.jpeg
Pictures with gradually varying tones (e.g., photographs) are successfully packaged in the jpeg format for use on the web.
.pdf and .ps or .eps
Use pdf or postscript when you aim to output a graph that can be accessed in isolation from your R Report.