Drag & Bounce Application Technology

You may have noticed when you're using the Safari on iPhone, you can touch and drag the application away from the screen (you'll see gray background), but it quickly spring back to the original position. Just before it lock down, it bounces just a little. The bounce is more noticeable at the end of the Contact list, when you try to flick past the end.

1. What drives the drag (not touch screen) technology? Can this same thing be created for a web site?
2. What drives the bounce effect? What is the formal name for this? Can this be done for a web site?