R is a statistical language and software for data analysis and graphing. It is an open-source implementation of the S language which was developed at Bell Laboratories (formerly AT&T, now Lucent Technologies) by John Chambers and colleagues. Therefore, much code written for S runs directly under R.
R is built through packages, including the base package and thousands of extended packages or extensions.This base package contains the basic functions which let R function as a language: arithmetic, input/output, basic programming support, etc. It allows the creation of extension packages based on it. With the base and the extensions, many statistical data analysis can be conducted and high quality statistical graphs can be produced.
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 UNIX platforms and similar systems (including FreeBSD and Linux), Windows and Mac OS.
R is now widely used by both statisticians and applied researchers for good reasons.
R can be installed on different operating systems.
R is most easily used in an interactive manner. You ask it a question and R gives you an answer. Questions are asked and answered on the command line. To start R, the following procedure can be used.