R, also known as GNU S, is a free statistical and graphics language and environment. It is similar to the S language, and is written for Unix, Windows, and Mac.
R is available on Apps@Stern, the Stern Citrix server. It is also available to Students through the NYU Virtual Computer Lab (VCL), the NYU Citrix server. R can be downloaded free and installed locally, as well. See link below.
The R Project for Statistical Computing