This post describes how to download and perform a basic local install of R and Rstudio. The instructions should work for both macOS and Windows users. Although not required, installation tends to work best when operating systems are up-to-date. At the time of writing, this means R/Rstudio work best with macOS High Sierra and Windows 10.

## R vs Rstudio

R is a statistical computing language/environment. It is distinct from Rstudio, which is an integrated development environment (IDE) or high- powered graphical user interface (GUI) optimized for working with the R language. In other words, R is the engine, and Rstudio is the interface. Consequently, you’ll need to install both R and Rstudio.

Use the following instructions to download and install the R statistical computing language/environment:

1. Go to the CRAN (Collective R Archive Network) website: https://cran.r-project.org/
2. Click on the appropriate operating system (Mac or Windows) to navigate to download page.
• If Mac, select the first .pkg file listed in the “files” section. At time of writing, this is version R-3.5.1.pkg.
• If Windows, select the bold, underline link written as ‘install R for the first time’.
4. Double click (run) the downloaded file (check your Downloads folder). Click yes through prompts to install like any other program (default values should be okay). You may get a warning about the source of the download being unkown. Do whatever you can to allow the installation to continue—I promise the R pkg file is safe!

Rstudio is an integrated development environment (IDE) that makes it easy to use R. Once both R and Rstudio are installed, I’d actually recommend ignoring the actual “R” program and instead only open and use Rstudio, which will automatically call and allow interactive use of R.

3. Double (run) click the downloaded file (check Downloads folder). Click yes through prompts to install like any other program (the defaults should be fine). You may get a warning about the source of the download being unkown. Do whatever you can to allow the installation to continue—I promise the R pkg file is safe!
You should be able to find the Rstudio application in your computer’s Application or Program folder. Alternatively, a simple search for “Rstudio” using finder/spotlight or the Windows key should be able to locate “Rstudio” on your machine.