XMLHttpRequestin the raw browser object that jQuery wraps into a more usable and simplified form and cross browser consistent functionality.
All jQuery functions use
XMLHttpRequestobject in the background, but provide additional functionality that you don't have to do yourself.
jQuery.ajaxis a general Ajax request in jQuery that can do any type and content requests.
jQuery.postcan only issue GET and POST requests. Internally these two functions use
jQuery.ajaxbut they use particular settings that you don't have to set yourself thus simplifying GET or POST request compared to using