Symbols & colors

# plot data as colored circles

plot(height ~ width, data = mydata, pch = 21, bg = 'blue')

# check available colors

colors()

# check for different kind of blue

grep("blue",colors())

read more

The R color palette

https://github.com/EarlGlynn/colorchart/wiki/Color-Chart-in-R

Colors and symbols in R figures

http://www.statmethods.net/advgraphs/parameters.html