JQuery/Javascript process question -

I inherited someone else's project and preparing a work flow diagram for this. Without getting too much information, the person left was the only person with advanced programming skills in the web program (most people work there and some HTML / CSS stuff). The legacy project I was developed was developed in Codeigner and Janet, AJX and JSON were heavily tampered with. The flow is a bit confused, so this is my profile. (I'm getting the question, bear with me)

Still, the manager of this department, let's look at him as a tool, will not allow his people to learn all this. He asked me the next day how it was coming and I said okay, except I do not know where a variable is being set up, using the jquery to set the path of the file to the original developer call some form value (He's using #id Val ()), but I can not find #ID anywhere in the code. The manager replies, eh, I thought that you were a PHP master. As I said, we will see it as a tool.

Nevertheless, to touch her something, I have decided to share these flow pages with the people of my group to some extent, make them very descriptive and hopefully educational. I am convinced that when a change is made from a selection menu, then jquery / javascript recognizes that the code will change and fire the corresponding code in js.

Then I came to know that I did not really know how JS / JQ knew that the change had been done. I know that code ($ ("# id"). Change () ... I have an applet background and there is a waste command in that language, basically you can see a script sitting in the background and X (Waiting for the user to launch Photoshop) and when that event is done, the rest of the code is run. Does JS do this?

This code:

  $ ("# id" JQuery ("$") describes the element whose "id" is the value (in this case), "id", and then the element on a " Change "to trigger the event. Event components will be registered to view such developments that run on that element. Based on what Javascript does in a browser, the basis: Events responses.  
 Somewhere, maybe one of them:  
  $ ("# id"). (Function () {...}) $ ("# id") Live ('change', function () {...}) $ ("# id"). Bind ('change', function) { ...})   
 There are several ways to identify elements for event handlers, however, it can be difficult to find.