A *(collection-oriented) *(programming language) and environment for statistical computing and graphics.

From its homepage:

<blockquote>
R is `GNU S' - A language  R is similar to the award-winning S system, which was developed at Bell Laboratories by John Chambers et al. It provides a wide variety of statistical and graphical techniques (linear and nonlinear modelling, statistical tests, time series analysis, classification, clustering, ...).
</blockquote>

<ul class="links">
  <li>_("The R Project for Statistical Computing"|http://www.r-project.org/).</li>
  <li>_("The Comprehensive R Archive Network"|http://stat.ethz.ch/CRAN/).</li>
</ul>
