Salt:
This should be a very long string of (preferably random) characters, the longer the string the less likely it will be crackable
Service/Site:
This can be the name of the service your making a password for, for extra security add an extra few characters to the end - these can be the same for all your passwords
Password:
I can't guarantee this site hasn't been modified on its way to you so you might want to check the code , you should be ok if your browser shows this as a https connection. However because of this you should treat this site as experimental and therefore using it may risk your security.