Why include jQuery files

[eacfje]

I'm looking at the instructions:

Download the archive
Unzip archive
Locate the folder custom-theme inside the css folder inside the newly uncompressed file
Move that folder inside the css directory of the website for which you want to use jquery-ui-bootstrap
Include the appropriate .css files in the layout of your website

I'm not understanding why, if only the css directory is used, there are jQuery, assets and third-party folders. I'm new to Bootstrap and have been tasked with a project to convert from jQuery UI to Bootstrap and this github project has been mentioned as an interim solution. So, why the "unused" folders? They must be there for some reason.

[tiesont]

Those resources are all for the demo site.