How to submit data to a server-side script and then display the output within a webpage without submitting the entire webpage?
Why not just look at how Gmail does it ?
Nice example here too of a web page requesting more content after it has loaded: http://developer.apple.com/internet/webcontent/XMLHttpRequestExample/example.html
I wrote something about this in my "html carol" post. Yes you can use a hidden iframe/object as your RPC bridge. The response can contain script to modify elements of your web page's interface and so on.
Here is another good explanation/tutorial about using IFrames. By the way, if you're wanting to Google about this stuff, I believe the concept is called "Remote Scripting".
Trouble with iframes is that annoying click that IE makes when it reloads.
Netflix does this with the star rating system (click 3 stars and poof, you've rated the movie - no page refresh). Amazon does this now.
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