How to change the short user name in OS X

Question

I'm using a Macbook Pro and I'm wondering how to change the short name of the "user account"?

Answer 1

I am not sure whether this is what you are after, but by dropping into System Preferences > Accounts, you can change the Full name for any of the available users you have access over.

Apple has a KB article explaining how the short name as well as the directory name for a user can be changed.

I will cite the instructions to change the short name from the article for versions of OS X 10.5 and later:

1. Enable the root user.
2. Log in as root.
3. Navigate to the /Users folder.
4. Select the Home folder with the short name you want to change, and rename it just like you would rename any folder. Keep in mind that the shortname must be all lowercase, with no spaces, and only contain letters.
5. Use the Accounts pane in System Preferences to create a new user with the short name that you used in the previous step.
6. Click OK when "A folder in the Users folder already has the name 'short name'. Would you like to use that folder as the Home folder for this user account?" Note: This will correct the ownership of all files in the Home folder, and avoid permissions issues with the contents.
7. Choose Log Out from the Apple menu.
8. Log in as the newly created user. You should be able to access all of your original files (on the desktop, in Documents, and in the other folders of this Home).
9. After verifying that your data is as expected, you can delete the original user account via the Accounts pane of System Preferences.
10. Disable the root user.

Answer 2

If your Mac was a school, a Standard User would be equal to a student, an Administrator would be equal to a Teacher, and root would be equal to the Principal. You can add, move, and delete files without the system complaining much because you're the Boss.

Of course, this means you can screw things up royally. Be careful.

This is Apple's article on how to enable Root: http://support.apple.com/kb/ht1528

I hope that helps!