"Documents, examples, tutorials and resources on R and data mining." Various topics touched upon. Does not go very deep into each topic. Some sections in construction. Also provides links to further documents and books.
Search all R packages and function manuals. Same help pages as with the ? command, presented in a nicer way. Provides more search options as well as the possibility to comment on packages etc.
Online book to take your R (programming) skills to the next next level. The authors is quite influencial in the R community and "knows what he's talking about". This is for advanced R users!