Permission

rwx r- - r- -

file/ user group others

folder (d) [ * r-> readonly, w -> write, x -> execute]

# chmod u+rwx, g+rw, o+r file_name [to add permission, where user can do everything & group user can read and write & others can read only]

# chmod u-x, g-w, o-r file_name [to eliminate permission]

# chmod ugo+rwx file_name [to give all permission to all users]