An intro to R for new programmers by Scott Chamberlain.
From the webpage:
This is an introduction to R. I promise this will be fun. Since you have never used a programming language before, or any language for that matter, you won’t be tainted by other programming languages with different ways of doing things. This is good – we can teach you the R way of doing things.
Scott says this site is a rip off of JSforcats.com and I suggest we take his word for it.
If being “for cats” interests people who would not otherwise study either language, great.
Enjoy!