To find help on some topic : [root@SLES /]# man pwd or [root@SLES /]# info pwd Also you can seek for a particual keyword ( say: umask) in the man pages by: [root@SLES /]# man -K umask To find a file in the /usr directory, use: [root@SLES /]# find /usr -name “*.doc” To find files and directories owned by the group students in the /usr directory, use: [root@SLES /]# find /usr -group students Assuming a user left the organization and the files owned by his account name must be found and deleted for security reasons, use : [root@SLES /]# find / -user Shaheer -exec rm '{}' ';' Want to perform some quick mathematical calculations, use: [root@SLES /]# bc To set up date and time as 16 Jan 2000 17:35 you should use: [root@SLES /]# date 0520173503 To synchronize it with the hardware clock, use: [root@SLES /]# hwclock –-systohc To check for memory and swap space usage, you can use: [root@SLES /]# free or [root@SLES /]# top To check the sy...