Using common aesthetics for multiple geoms with ggplot2

How to map the same aesthetics to multiple geometries.

An html version of this material used in the video can be downloaded to your current working direction (run `getwd()` in the Console to see where this is) by running the following command in the R Console:

The raw R Markdown code used to generate the html file can be obtained by toggling the "Code" box in the upper-right corner of the html file and selecting "Download Rmd".