# chgrp group1 file1
change group of files [man]
# chmod ugo+rwx directory1
set permissions reading (r), write (w) and (x) access to users owner (u) group (g) and others (o) [man]
# chmod go-rwx directory1
remove permits reading (r), write (w) and (x) access to users group (g) and others (or [man]
# chmod u+s /bin/file1
set SUID bit on a binary file - the user that running that file gets same privileges as owner [man]
# chmod u-s /bin/file1
disable SUID bit on a binary file [man]
# chmod g+s /home/public
set SGID bit on a directory - similar to SUID but for directory [man]
# chmod g-s /home/public
disable SGID bit on a directory [man]
# chmod o+t /home/public
set STIKY bit on a directory - allows files deletion only to legitimate owners [man]
# chmod o-t /home/public
disable STIKY bit on a directory [man]
# chown user1 file1
change owner of a file [man]
# chown -R user1 directory1
change user owner of a directory and all the files and directories contained inside [man]
# chown user1:group1 file1
change user and group ownership of a file [man]
# find / -perm -u+s
view all files on the system with SUID configured [man]
# ls -lh
show permits on files [man]
# ls /tmp | pr -T5 -W$COLUMNS
divide terminal into 5 columns [man]