A multi-user computer environment designed to provide access to a range of computer applications, tools and utilities to the users of the system.                         Chart includes detailed information on:          * logging in/out          * UNIX shells & command line          * the UNIX file system          * redirection          * access permissions          * wildcards, printing& environmental variables          * finding files & directories          * electronic mail          * archiving files & directories          * remote connections          * job control          * File Transfer Protocol (FTP)          * editors          * command summary          * login/logout shells& scripts