The Repository
CRAN In particular, check out the links under "Documentation", i.e. → Documentation → Manuals etc.
The Interface
I recommend looking at the IDE cheat sheet to learn about navigating the R Studio environment and the rmarkdown cheat sheet to learn how to generate and structure R markdown files.
The latest versions of these cheat sheets are also available from within R studio, click on Help → Cheat Sheets.
Getting Started
Getting started with R and R Studio video.
SWIRL - learn R in R.
Roger's installation videos.
Roger's R environment videos.
Alyssa Frazee's R in an hour.
Michael Love's R Studio introduction video download [ 22MB ].
The Manual
Other R Resources
Andrew Jaffe's Introduction to R for Public Health Researchers.
A (very) short introduction to R
Peter Dalgaard's book via Springerlink.
John Verzani's SimpleR notes
- to run some of the examples in John Verzani's notes, it is helpful to install his R package:
> install.packages("UsingR")
> library(UsingR)
The Introduction to R course from DataCamp.