passwd sleepy Change sleepy's password.

passwd -d sleepy Delete sleepy's password.

When you enter one of these commands to change a password, you will be prompted for the old (current) password and a new password. Your new password should be at least six characters long and not too easy for someone else to guess. Oh, and writing it down on a scrap of paper taped to your monitor is not recommended either. :-)

If you share your Linux system with multiple users, or if you have a dial-in modem attached, password security for each account is particularly important. But if you're the only one who will ever lay a finger on your system, you might want to delete your password, thus removing the need to enter it each time you log in. It's your call, but you never know when your five-year-old will wander by the keyboard!

By the way, you might get the idea from the preceding commands that users can go around changing each other's passwords at will, but that's not the case. Only a superuser (such as root) can change or delete another user's password.

For more information on the passwd command, see the passwd manual.

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