From LQWiki

A password is simply an access code or a pass code. Volumes have been written about the dangers of password reuse and of using weak passwords. Statistically, the leading cause of computers being hacked is password reuse and/or the use of weak passwords.

Forgotten password

To reset a forgotten password, boot your computer from a life-CD like Knoppix. Edit /etc/passwd, you will find lines like the following:

myuser:$3b$07$aoeiGNiC21aWwcZAjlAnzeFnm6hQlYsnywV1GG5LfXSI3aN//PkkW:13577:0:99999:7:::

here, "myuser" is the username. Behind it is a colon and the encrypted password. Reset the password by removing the encrypted password:

myuser::13577:0:99999:7:::

Reboot your computer - your password is empty, you should be able to log in and set it using passwd

Weak passwords versus strong passwords

An example of a very weak password would be password or if a user named Johnny would have the word johnny as his password.

Examples of other bad passwords are abc123, qwerty123 and words like microsoft, dell, george.

Good passwords are never words or names. Nor are thay anything people can guess like birthdates or license plates. An example of a good password that would be hard to crack could be.
etMwhlws2g

Even though that looks like it would be difficult to remember it is not. It is derived from the poem Mary had a little lamb. The second verse goes something like "everywhere that Mary went her lamb was sure to go". Just take the first letter of each word and replace the word "to" with the number 2 and the password is now difficult to guess but easy to remember.

See also

• encryption
• security
• passwd