Keep in mind when using code below if requesting a page that requires login/restricted access, users login session is not carried over.

Snippet below is sample code usage illustrating two different methods of achieving similar result. See references for more info and full specifications.

Javscript (JQuery):

$.ajax({
                            url: 'http://www.websitename.com/',
                            dataType: "text",
                            type: "POST",
                            data: { city: "NewYork"},
                            error: function(err) {
                                alert("Error:" + err.toString());
                            },
                            success: function(data) {
                                //$("#JQuery_modal_p").html(data);
                                alert(data);
                            }

                        });

Javscript (JQuery):

$.ajax({
                            url: 'http://www.websitename.com/' + data1+ data2,
                            dataType: "text",
                            type: "GET",
                            data: {},
                            error: function(err) {
                                alert("Error:" + err.toString());
                            },
                            success: function(data) {
                                //$("#JQuery_modal_p").html(data);
                                alert(data);
                            }

                        });

References:
JQuery Ajax, http://api.jquery.com/jQuery.ajax/