ggplot2 Cheat Sheet:
One Variable: Continuous

library(ggplot2)

Area Plot

p <- ggplot(mpg, aes(hwy))
p <- p + geom_area(stat = "bin")
print(p)

Density Plot

p <- ggplot(mpg, aes(hwy))
p <- p + geom_density()
print(p)

Dot Plot

p <- ggplot(mpg, aes(hwy))
p <- p + geom_dotplot()
print(p)

Frequency Plot

p <- ggplot(mpg, aes(hwy))
p <- p + geom_freqpoly()
print(p)

Histogram

p <- ggplot(mpg, aes(hwy))
p <- p + geom_histogram()
print(p)

Q-Q Plot

p <- ggplot(mpg)
p <- p + geom_qq(aes(sample = hwy))
print(p)