It is a very simple and powerful ajax method to load the data from the server and display it in the selected element.

$(selector).load(URL,data,callback);

URL parameter specifies the URL you wish to load

data parameter specifies a set of querystring key/value pairs to send along with the request.

callback parameter is the name of a function to be executed after the load() method is completed.

ex

$("#div1").load("demo_test.txt");

We can also jQuery selector to the  url parameter.

$("#div1").load("demo_test.txt #p1");

callback parameter specifies a callback function to run when the load() method is complete

1. responseTxt - contains the resulting content if the call succeeds

2. statusTxt - contains the status of the call

3. xhr - contains the XMLHttpRequest object

$("button").click(function(){
    $("#div1").load("demo_test.txt", function(responseTxt, statusTxt, xhr){
        if(statusTxt == "success")
            alert("External content loaded successfully!");
        if(statusTxt == "error")
            alert("Error: " + xhr.status + ": " + xhr.statusText);
    });
});