Confused by custom downloads and layout of jQuery files.

Confused by custom downloads and layout of jQuery files.

I should start by saying Im not a front-end developer but Ive been forced to dive into JS and/or jQuery code to tweak the UI for our web app. Looking in our js folder it seems to me there is a mess of disorganized folders and JS files including jQuery and jQueryUI stuff. There seem to be several versions of these files which just add to the confusion. Also it looks like we have several custom versions of these files and no way of knowing which features were picked for the custom downloads. So, in order to bring order to chaos I need some help, specifically:

1) How are the jQuery UI files organized? What is the development-bundle folder? Do I ever need to include anything from the development-bundle folder?

2) Is there any way of looking at the files and figuring out what features were picked for a custom download?

Ive been trying to add the Resizable behavior but it looks like that class doesn't exist - so I went and downloaded the latest stable release and since I dont know what features were picked I ended up selecting everything and grabbing the ZIP.

3) I added the latest jQuery and jQuery UI to my template and have a function to switch on resizable for some input widgets but it doesn't work. My jQuery function looks like this:

$(function() {
    $( "#resizable" ).resizable();
});

And I have elements on the page with that ID but I dont see any resize handles appearing. Maybe I need to include some CSS?

I looked in the CSS folder we already have and the one from the new downloads and they have different folders in them: the older CSS folder has ui-lightness and custom-theme folders, while the new one just has a single folder called 'smoothness'. So it looks like Im missing some stuff to make this work...