R is an open source programming language and software environment for statistical computing and graphics. It is an implementation of the S programming language combined with lexical scoping semantics inspired by Scheme. R was created by Ross Ihaka and Robert Gentleman and is now developed by the R Development Core Team. It is easily extended through a packaging system on CRAN.
Official documentation from CRAN
- An Introduction to R PDF HTML - A basic introduction for beginners.
- The R Language Definition PDF HTML - A more technical discussion of the R language itself.
- Writing R Extensions PDF HTML - Guide to writing packages for R, help files and foreign language interfaces.
- R Data Import/Export PDF HTML - Guide to importing/exporting data in R in various formats.
- R Installation PDF HTML - Guide to installing R from source.
- R Internals PDF HTML - Outlines R's internal structures and coding guidelines for the R Core Team.
Other free resources
- The R Inferno (Patrick Burns) PDF
- R by example
- CRAN maintains an extensive list of free contributed documentation in a range of languages.
- R homepage
- List of CRAN Task Views, summary of useful packages per subject area.
- R tag chat on Stack Overflow
- How to make a great R reproducible example
Frequently asked questions:
R FAQ - Official list of R FAQs on CRAN