primarily an open-source programming language, provides an environment for performing statistical computing and graphics. It has a suite of software packages that can be used to accomplish a wide range of tasks such as data mining, time series analysis, machine learning, multivariate statistical analysis, analysis of spatial data, graphical plotting, etc.
R is an alternate implementation of the statistical programming language called S. S-PLUS was developed post S as its commercial version. R was introduced later by Ross Ihaka and Robert Gentleman in 1991. Though R is independent of S-PLUS, much of its code works without any alteration for R too. The first official version of R was released in 1995 as an open-source software package under the GNU General Public License.