I attempted unsuccessfully to download a copy of jQuery so I could find out what's on it. For some reason it won't download on my computer. I don't exactly why.

   When I run Google's Pagespeed Insights it keeps singling out plugins that use Jquery. I take it the fundamental problem is that the server has to go outside of the domain to look for code somewhere else. Even plugins that have relatively little code get blamed for significantly harming pagespeed if they make extensive use of jQuery.