9.6 Manually setting aesthetic propoerties

• We can also set the aesthetic properties of your geom manually. For example, we can make all of the points in our plot blue.
• The color doesn’t convey information about a variable, but only changes the appearance of the plot.

ggplot(mpg, aes(x = displ, y = hwy)) + 
  geom_point(color = "blue")