jquery ajax contenttype datatype,javascript - Differences between contentType and dataType in jQuery...

I have the following Jquery callback function and I have a litle doubt about it (I don't know very well Jquery):

$("form.readXmlForm").submit(function() {

// Riferimento all'elemento form che ha scatenato il submit

var form = $(this);

// Variabile che contiene il riferimento al bottone clickato

var button = form.children(":first");

$.ajax({ // Viene eseguita la chiamata AJAX

type: "POST", // Tipo di richiesta: POST

// URL verso quale viene inviata la richiesta

url: form.attr("action"),

// Dati XML inviati:

data: "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>barapple",

// Tipo di media type accettabile dalla response:

contentType: "application/xml",

dataType: "text",

success: function(text) {

MvcUtil.showSuccessResponse(text, button);

},

error: function(xhr) {

MvcUtil.showErrorResponse(xhr.responseText, button);

}

});

As you can see this function simply execute an AJAX Request to the backend setting the parameter for this request.

I have set that I am sending the request towards an URL, that the request is a POST request and that the data that I am sending are the following string:

"barapple"

I have some difficulties to understand what is the differences between contentType and dataType

I think that contentType specify the type of data that are acceptable recived in the HTTP Response, is it right?

And dataType? What say? The type of data that I am sending in the HTTP Request?

In this case is is "text" because I am sending a textual string that rappresent XML code?