Command line utilities for managing users and groups
useradd, userm od, userdel > Standard utilities for adding, modifying, and deleting user accounts.
groupadd, groupmod,groupdel > Standard utilities for adding, modifying, and deleting groups.
gpasswd > Standard utility for administering the /etc/group configuration file.
pwck, grpck > Utilities that can be used for verification of the password, group,and associated shadow files.
pwconv, pwunconv > Utilities that can be used for the conversion of passwords to shadow passwords, or back from shadow passwords to standard passwords
