Master Password Tool takes a single password of your choice (master password) and makes different, secure passwords off it for various popular web services like Gmail, Facebook, Twitter and so on. These passwords will only change when the master password is changed.
If you are only looking to get random, secure passwords, try the Random Password Generator Tool else use this tool. Please see FAQ for more information.
Important : Remember master password! It is also case sensitive. So using uppercase will result in totally different set of passwords than using lowercase. For sites not listed below, enter the master password as usual, then enter the site name in "Custom sites" box and hit the second Generate button ("Generate for custom sites")