The ExecuteScript and InvokeScript methods of a WebPage control are two ways to use your own JavaScript within a web page that you have interrogated with Pega Robotics. The ExecuteScript is used to either run some JavaScript that does not return anything, or to create a function that you'll later call with InvokeScript.

As for specifics about JQuery, as far as I know, the page would likely have already needed to import the libraries. If so, then you could execute those functions. This is all outside of the use of the product though, so you'll likely be dealing with a lot of this on your own.