I'm going to assume that you're smart enough not to use any of the following or anything similar as your passwords.
- Your partner, child, or pet's name, possibly followed by a 0 or 1 (because they're always making you use a number, aren't they?)
- The last 4 digits of your social security number.
- 123 or 1234 or 123456.
- Your city, or college, football team name.
- Date of birth – yours, your partner's or your child's.
A decent article on internet security and passwords is here.