Tidyverse book (Hadley Wickham)
seankross.com/notes/dpqr/
Quick intro to ggplot2 (Andy Grogan-Kaylor)
ggplot2 for beginners
patchwork (graph layouts)
ggplot customization cheat sheet
slides for ggplot course
ggplot book (Wickham, Navarro, Pedersen)
Graph Gallery
Graph Gallery2
Normal distribution functions (Sean Kross)
Stats as linear models (Jonas Kristoffer Lindelov)