If you want to quickly create a new user account in your Unix OS, it ca be done with just one line
Adding new user accounts in Unix
To create a basic Unix user account with default settings, you need to know only one thing: the username.
The reason I say it as one word is because username (quite often referred to as "login") is not the actual name of the new person gaining access to your Unix system, but rather a single keyword uniquely identifying this user in your system. Most often, usernames are derived from real names of users – jsmith, johns or smithj for John Smith, just to give you a few examples.
The simplest way to add a new user to your system is to do run a command like this:
ubuntu# useradd jsmith
If you don't get any errors thrown back at you, this means your command was executed successfully and you now have a new user. Use this command to verify:
ubuntu# finger jsmith Login: jsmith Name: Directory: /home/jsmith Shell: /bin/sh Never logged in. No mail. No Plan.
If you attempt to create a user with existing username, you'll obviously get an error:
ubuntu# useradd jsmith useradd: user jsmith exists
Setting a password for the newly created user account
Once you have created new user, you'll most likely need to have a new password assigned to it. Here's how you do it:
ubuntu# passwd jsmith Enter new UNIX password: Retype new UNIX password: passwd: password updated successfully
As you can see from the example, you'll be asked to type the new password twice, and it will be assigned to the user only if both inputs match.