From CCRMA Wiki
Changing Your Password
You may change your password at any time using the 'passwd' command in your login shell. You will be prompted to enter your old password then to enter your new one, twice. Please see below for guidance on how to choose intelligent passwords. If you forget your password, you will need to see the System Adminisrator.
From the 'passwd' man page:
Remember the following two principles Protect your password. Don’t write down your password - memorize it. In particular, don’t write it down and leave it anywhere, and don’t place it in an unencrypted file! Use unrelated passwords for systems con- trolled by different organizations. Don’t give or share your password, in particular to someone claiming to be from computer support or a vendor. Don’t let anyone watch you enter your password. Don’t enter your password to a computer you don’t trust or if things Use the password for a limited time and change it periodically. Choose a hard-to-guess password. passwd will try to prevent you from choosing a really bad pass- word, but it isn’t foolproof; create your password wisely. Don’t use something you’d find in a dictionary (in any language or jargon). Don’t use a name (including that of a spouse, par- ent, child, pet, fantasy character, famous person, and location) or any variation of your personal or account name. Don’t use accessible information about you (such as your phone number, license plate, or social security number) or your environment. Don’t use a birthday or a simple pattern (such as backwards, followed by a digit, or preceded by a digit. Instead, use a mix- ture of upper and lower case letters, as well as digits or punc- tuation. When choosing a new password, make sure it’s unrelated to any previous password. Use long passwords (say 8 characters long). You might use a word pair with punctuation inserted, a passphrase (an understandable sequence of words), or the first letter of each word in a passphrase. These principles are partially enforced by the system, but only partly so. Vigilence on your part will make the system much more secure.