R is a programming language developed by data analysts for data analysts. It offers many features that make a powerful tool for data exploration. Some basic features need to be understood to begin programming in R. The following presentation covers some of these features including working with variables, vectors and data.frames. It also covers reading and writing data from/to files, plotting and installing R packages (and getting help for the packages.
Slides: Using R: http://slides.lunean.com/uspWorkshop/usingR.pdf