JQuery Command/Method Question

JQuery Command/Method Question

I'm very new to JQuery and am trying to get a test page to work using code found in a DOTCMS/JQuery tutorial. As part of the tutorial I have the following piece of code in one of the code blocks:
 
       var url = "test-ajax-products-page.html";
 
       ${esc.d}.ajax( { url: url, type: "GET", data: "cat="+cat, dataType: "html", success: function(data) {
${esc.d}('${esc.h}productSearchResults').html(data);}});
 
I'm not sure I completely understand what this part:
 
${esc.d}('${esc.h}productSearchResults').html(data);
 
is actually supposed to do with the data or what it is expecting the data to be, and so far haven't been able to find anything much on what ".html()" does exactly, or other alternatives to using it. Can someone please clarify this or possibly point me to information on ".html()" or other alternatives to it?