Commands and files related to uwers and groups.

$ cat /etc/passwd
$ cat /etc/group
$ cat /etc/default/useradd
$ cat /etc/login.defs
$ ls -a /etc/skel
$ less /etc/profile

• useradd, usermod, userdel
• groupadd, groupmod, groupdel
• passwd
• newusers
• chage

Afterwards, check:

$ grep username /etc/passwd
$ grep username /etc/group
$ ls /home