checklist

The Best Online R Textbooks	Statistics Textbooks Online

Introduction to the R Project for Statistical Computing for use at ITC by Rossiter (3.0 MB) (PDF)
The R Guide by Owen (467 KB) (PDF)	Introduction to Probability and Statistics Using R by Kerns (PDF)
simpleR – Using R for Introductory Statistics by Verzani (PDF)	Practical Regression and Anova Using R by Faraway with R examples (PDF)
An Introduction to R by R's Core Development Team (HTML)	Introduction to Statistical Thought by Lavine (43MB) with R examples (PDF.gz)
icebreakeR by Robinson (3.6 MB) (PDF)	Introduction to Probability by Grinstead and Snell with Matlab examples (PDF)
An Introduction to R: Software for Statistical Modelling & Computing by Kuhnert and Venables (4.5 MB zip file)
	Debugging
R Graphics Textbooks	Put a call to browser() in the function of interest.
R Graphics by Paul Murrell (HTML)	After an error message try traceback()
Using R for Data Analysis and Graphics Introduction, Code and Commentary by Maindonald (PDF)	Try binary search

Web Search	R help functions
RSiteSearch by Jonathan Baron	apropos('regexp') # Search for loaded symbols (functions, etc.)
Rseek.org by Sasha Goodman	help(functionname) # Tells how to use the function
	help.search('regexp', agrep=F) # Search the help system database fields
For Hard Questions	help.search('pattern') # Search help db using Levenshtein edit distance
Official R Manuals	library() # Shows loaded packages
Frequently Asked Questions	library(packagename) # Loads the package
CRAN Task Views	vignette('packagename') # Overview of package
Other Contributed R Documentation	ls(package:packagename) # Functions in package
	ls() # Shows currently defined local functions & variables
	search() # shows things on the search path
	args(functionname) # Shows the names of the function's arguments