Why does this work?

Why does this work?

Hi, I have a question that puzzles me a lot. I have the following code:

$(document).ready(function() {
    $("#somediv").load("/some/content");
})


The code inserted with AJAX contains two things.
1. A script tag that states things like:
$("#Cancel").click(function(e) {
        e.preventDefault();
        alert("you cancled");
    })

2. A div with various elements, like the button with ID "Cancel".

When I click that Cancel button, the alert executes just like I want it to do. But I can't figure out why?? I mean how can the eventhandler register correctly. Is the Cancel button from the AJAX call somehow magically insert into the DOM before the script registering the event executes?