I include the following two reference files that I developed for a stats class in linguistics.
R command reference: This document lists upwards of 100 functions covering basic statistical operations in R, as well as some basic operators and their use.
Statistics glossary: This document presents about 90 statistical terms, with definitions. Pointers to R commands relevant to those terms are included where possible.
These are works-in-progress, and I welcome any feedback aimed at helping me improve them so that they may be useful to students, teachers, and users of statistics.