How to create user without useradd command in Linux

Follow these steps to create a user without using useradd command in Red Hat Linux.

Step 1
Add an entry of user details in /etc/passwd
# vi /etc/passwd
user:x:501:501:test user:/home/user:/bin/bash
Step 2
You will have to create a group with same name. So add a new entry in /etc/group
# vi /etc/group
user:x:501:
Step 3
Assign a password to the user
# passwd user
Changing password for user user.
New password:
Retype new password:
passwd: all authentication tokens updated successfully.
Now let us try to login with our newly created user
# su - user
-bash-4.1$
You should see [user@test ~]$ instead of -bash-4.1$ prompt. So why does this happens?

Let us check the contents of its home directory
-bash-4.1$ ls -al
drwxr-xr-x 2 root root 4096 Jan 12 14:27 .
drwxr-xr-x. 3 root root 4096 Jan 12 14:27 ..
So, as you see none of the default contents of a normal user home directory is missing.

Final Step 4
NOTE:/etc/skel directory contains all the defaults files which are present inside the home folder of any user

So, copy the contents from /etc/skel inside /home/user using the below command
[root@test ~]# cp -v /etc/skel/.* /home/user/
cp: omitting directory `/etc/skel/.'
cp: omitting directory `/etc/skel/..'
`/etc/skel/.bash_logout' -> `/home/user/.bash_logout'
`/etc/skel/.bash_profile' -> `/home/user/.bash_profile'
`/etc/skel/.bashrc' -> `/home/user/.bashrc'
`/etc/skel/.emacs' -> `/home/user/.emacs'
cp: omitting directory `/etc/skel/.gnome2'
cp: omitting directory `/etc/skel/.mozilla'
Now re login to the user
[root@test user]# su - user
[user@test ~]$
And you are good to go.

IMPORTANT NOTE: But one more thing, did you noticed I didn't touched /etc/shadow file while it also contains all the user related details. As soon as we assign a password to the user an entry for that user is created inside /etc/shadow

NOTE: Do not manually edit /etc/shadow file because it contains the encrypted password section which is automatically generated
# cat /etc/shadow | grep user
user:$6$HG.agA9Q$X2scLxur6G6FIW0eb1ArgAQcnioNLJmeBjDX.FAvfchXUhElwVKhwa3hHCFMI/vNUdr3fgqcge2PTEaKFfzXW/:16082::::::
Let me know your success and failures