Installing Packages

R comes with a basic set of commands. These are stored in base R and always load when you open RStudio.

However, the range of functions in base R is fairly small. One of the best things about R is its thousands of user-created packages. Basically, people who wanted to be able to do something in R created new sets of commands to make it happen.

To use functions in packages other than base R:

• First, install the package you want with the install.packages command. For example, if the package is called "package", then just:

    install.packages("package")

R will likely ask you which "CRAN Mirror" to install the package from. Just follow the on screen instructions to choose the mirror that is geographically closest to you.

• Second, load the package using the library command:

   library(package)

In general you will need to use library(package) each time you want to use the package per R session.