% printenv | less

UNIX Tutorial Eight 
    * OSTYPE (OS type)
    * USER (your login name)
    * HOME (the path name of your home directory)
    * HOST (the name of the computer you are using)
    * ARCH (the architecture of the computers processor)
    * DISPLAY (the name of the computer screen to display X windows)
    * PRINTER (the default printer to send print jobs)
    * PATH (the directories the shell should search to find a command)