Creating a personal library for R packages - Macintosh.

1. Navigate to your home directory. In the Finder, use Go -> HOME
   
2. Create a new directory (folder) for the R pacakges. Traditionally this is called Rlibs
   
   
3. You now want to create a special (hidden) file called .Renviron (yes it beings with a period) that contains a single line
       R_LIBS=~/Rlibs
   This will tell R that your personal (package) library is the directory called Rlibs in your home directory.

   To create the .Renviron file will require a litte work with the Terminal application.

4. Launch the Terminal application: Go -> Applications -> Utilities -> Terminal
   
   
   This gives a window looking similar to:
   
   
5. Type the unix command
      ls
   to list the files in your home directory. You should see the Rlibs directory that you created earlier.
   
   
6. Type the unix command (or copy and paste the line below)
       echo "R_LIBS=~/Rlibs" > .Renviron
   Don't forget the period (.) before the Renviron name and besure that your case matches.
7. Type the unix command
       ls -a
   to see all of the files in your directory, including those with an initial period. You should now see a .Renviron file in the listing. Don't worry about the other files.
   
8. Finally, type the unix command to verify that the .Renviron file has been set properly:
       more .Renviron