What documentation exists for R?

Chapter 5: R Add-On Packages 56
riv Robust Instrumental Variables estimators based on high breakpoint point Sestimators
of multivariate location and scatter matrices.
rjacobi Jacobi polynomials and Gauss-Jacobi quadrature related operations.
rlecuyer R interface to RNG with multiple streams.
rmeta Functions for simple fixed and random effects meta-analysis for two-sample
comparison of binary outcomes.
rmetasim An interface between R and the metasim simulation engine. Facilitates the use
of the metasim engine to build and run individual based population genetics
simulations.
roblm Robust regression estimators.
robust Insightful robust package.
robustbase
Basic Robust Statistics.
rpanel Simple interactive controls for R using the tcltk package.
rpart Recursive PARTitioning and regression trees. Recommended.
rpart.permutation
Permutation tests of rpart models.
rpubchem R interface to the PubChem collection.
rpvm R interface to PVM (Parallel Virtual Machine). Provides interface to PVM
APIs, and examples and documentation for its use.
rqmcmb2 Markov chain marginal bootstrap for quantile regression.
rrcov Functions for robust location and scatter estimation and robust regression with
high breakdown point.
rrp Random Recursive Partitioning.
rsprng Provides interface to SPRNG (Scalable Parallel Random Number Generators)
APIs, and examples and documentation for its use.
rstream Unified object oriented interface for multiple independent streams of random
numbers from different sources.
rtiff Read TIFF format images and return them as pixmap objects.
rv Simulation-based random variable object class.
rwt Rice Wavelet Toolbox wrapper, providing a set of functions for performing
digital signal processing.
sac Semiparametric empirical likelihood ratio based test of changepoint with onechange
or epidemic alternatives with data-based model diagnostic.
sampling A set of tools to select and to calibrate samples.