What documentation exists for R?

Chapter 5: R Add-On Packages 38
deldir Calculates the Delaunay triangulation and the Dirichlet or Voronoi tesselation
(with respect to the entire plane) of a planar point set.
delt Estimation of multivariate densities with adaptive histograms.
denpro Visualization of multivariate density functions and estimates with level set trees
and shape trees, and visualization of multivariate data with tail trees.
depmix Dependent Mixture Models: fit (multi-group) mixtures of latent Markov models
on mixed categorical and continuous (time series) data.
dglm Double generalized linear models.
diamonds Functions for illustrating aperture-4 diamond partitions in the plane, or on the
surface of an octahedron or icosahedron, for use as analysis or sampling grids.
dichromat Color schemes for dichromats: collapse red-green distinctions to simulate the
effects of colour-blindness.
digest Two functions for the creation of “hash” digests of arbitrary R objects using the
md5 and sha-1 algorithms permitting easy comparison of R language objects.
diptest Compute Hartigan’s dip test statistic for unimodality.
dispmod Functions for modelling dispersion in GLMs.
distr An object orientated implementation of distributions and some additional functionality.
distrDoc Documentation for packages distr, distrEx, distrSim, and distrTEst.
distrEx Extensions of package distr.
distrSim Simulation classes based on package distr.
distrTEst Estimation and Testing classes based on package distr.
distributions
Probability distributions based on TI-83 Plus.
diveMove Dive analysis and calibration.
dlm Maximum likelihood and Bayesian analysis of Dynamic Linear Models.
doBy Facilities for groupwise computations.
dprep Data preprocessing and visualization functions for classification.
dr Functions, methods, and datasets for fitting dimension reduction regression,
including pHd and inverse regression methods SIR and SAVE.
drc Non-linear regression analysis for multiple curves with focus on concentrationresponse,
dose-response and time-response curves.
drfit Dose-response data evaluation.
dse Dynamic System Estimation, a multivariate time series package bundle. Contains
dse1 (the base system, including multivariate ARMA and state space
models), dse2 (extensions for evaluating estimation techniques, forecasting, and
for evaluating forecasting model), tframe (functions for writing code that is
independent of the representation of time), and setRNG (a mechanism for generating
the same random numbers in S and R).