Customising the environment.
Users can customize their environment in several different ways.
There is a system initialization file and every directory can have its own special initialization file. The system initialization file is called Rprofile and it is found in the home subdirectory library. This file should contain the commands that you want to execute every time is started under your system. 12 can be placed in any directory. If is invoked in that directory then that file will be sourced.