This is a bit of background material to place R in broader context. It is optional.
R was developed in the late 1980s in New Zealand by Ross Ihaka and Robert Gentleman, known as R & R. It was built on LISP language ideas adopting the syntax of the S language, which was in turn created by John Chambers and colleagues at AT&T in the 1970s. While S was proprietary, limiting distribution, R has been freely available and open source since the beginning. Since the 1997, R has been maintained by a core development team of about 20 people. For more information, see https://www.r-project.org/about.html.
Originally, R ran on a “dumb” terminal. There were many efforts to build a useful graphical user interface, or GUI. RStudio was founded in 2008 with public release in 2011, and was quickly adopted by the R community. See https://www.rstudio.com/about/.