Here's the ultimate dictionary, glossary,and thesaurus for the R language
The cross-platform, open source language R provides powerful tools for data analysis and reporting, but its complexities can be a bit daunting. To use the built-in help system, you must know the command names the vocabulary and grammar of R. This book contains more than 400 command names arranged by topic, with plenty of examples, related commands, and cross-references. It's the quintessential resource for R beginners and veterans alike.
You will find:
Commands grouped by theme, letting you search for one based on the task you wish to accomplish
Explanations showing what each command does
Commonly used parameters for each command
Examples and related commands
Cross-references for command names with multiple applications