PHP & Forms & AJAX... How do I create a calculator....

[fkatzenb]

I am trying to create a form with several user inputs. I then want to automatically update a series of fields automatically with or without a calculator button. Preferable the first. The output fields can be part of a form or just plain text. Later is preferable. how do I do this? I know how to create basic forms and do 'post', but that is it.

I am a newbie.


Thanks!

Frank


EDIT:
I just updated the title... I now know a little bit more... basically I need to create a calculator using AJAX that works like this...
http://www.standards-schmandards.com/exhibits/ajax