What is R?
"R" has two connotations. First, it is an open-source statistical package; second, it refers to a computer programming language known as R. You may download and install whichever version you'd like at http://www.r-project.org. Extensive guides for downloading R to a Windows machine and to a Mac machine also exist. Boasting a robust open-source community as one of its assets, R has a lot of online and built-in help.
Tutorials and Help Guides for R
As economists would say, there are significant start-up costs to learning R. It can be daunting. Resources, like this PDF, can help those users who would like a document to help them started. The Appendix on sources of help and documentation should prove helpful.
This site is also useful.
For answers to specific R-related questions, try using this resource, though Google searches can be equally fruitful. If you would like more direction than this for R, just let me know. If R is too strong a brew of tea, check out Paula Lackie's data page and research methods support site.
Other notes
Past complaints about R involved file size limitation (due to hardware constraints). This is no longer an issue.
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