How to change password on a pdf document?

i have a pdf with the password on it and i want to change it quick, how?How to change password on a pdf document?
Hi, I think that the best is to save it again with a different password.

You need to:

1. open pdf

2. type your password

3. click file-%26gt; save as

4. than you can see menu with password options

5. change it to yours

hope it was informative =) if it was than please vote for my answer =) thanksHow to change password on a pdf document?
I'm assuming you are using Adobe. If you know the original password, go Preferences, Security Options, then edit your password settings.