command: who usage: show who is logged on options: who [option]... [ file | arg1 arg2 ] examples: 1. To print all information regarding who is logged in $ who -a 2. To print time of last system reboot $ who -b 3. To print finish processes $ who -d 4. To print only hostname and user associated with stdin $ who -m 5. To print active processes spawned by init $ who -p 6. To print all login names and number of users logged on $ who -q 7. To print current runlevel $ who -r 8. To print only name, line, and time $ who -s 9. To print last system clock change $ who -t 10. To add user's message status as +, - or ? $ who -T 11. To list users logged in $ who -u 12. To print help info of this command $ who --help regards, dhanasekar