R is a language and environment for statistical computing and graphics which provides a wide variety of statistical techniques, including linear and nonlinear modeling, classical statistical tests, time-series analysis, classification, clustering, etc. The program uses graphical techniques, and is highly extensible. R is similar to the S language and environment developed at Bell Laboratories (now Lucent Technologies), and most S code also runs in R.
R is available as Free Software under the terms of the Free Software Foundation’s GNU General Public License in source code form. It compiles and runs on a wide variety of platforms, including Window,s MacOS, UNIX, FreeBSD, and Linux.
Tutorials - Paired Sample T Test
Tutorials - One Sample T Test
Tutorials from Universities
Tutorials - Independent Samples T-Test
Tutorials - One-Way ANOVA
Tutorials - More One-Way ANOVA