R comes in multiple flavors. The heart of the software is a command-line interface (CLI) that is very similar to the BASH shell in Linux or the interactive versions of scripting language like Ruby or Python. The Window version of R supports multiple GUIs.
The default GUI is invoked by simply invoking the R program either via the command line or via the Windows GUI. Within R, the rcmdr interface offers a more task-oriented view. The Rattle interface is another framework that is more task oriented: a user can load a dataset and automatically perform certain tests.
Finally, RStudio provides both a desktop and a Web browser interface. This is the UI that we will be using in this course. RStudio offers three panes that are fairly common to all R GUIs The upper left pane is for script editing. The lower left pane is the R console itself, where all commands are executed.
The lower right pane is the help screen, invoked by the help() command, with which you will become very familiar, as well as tabs for file in the current directory, plots, and a tab that enables you to view which packages are available locally or can be downloaded from CRAN, the comprehensive R archive network. Finally, the upper right pane is unique to RStudio, and offers a table-oriented view of the variables stored in the current R workspace. Clicking on a variable or data structure in the workspace window will display the values of that object in the script window as a separate tab.
Note that many panes have multiple tabs that offer different views on the workspace: take a moment to familiarize yourself with their content during our first lab. Each pane can be grown or shrunk by clicking on the grow boxes in the upper right hand corner of each pane