What is the difference between JSON and AJAX with jQuery?

Question

I've heard that JSON serializes all the data, which stops me having problems client side in terms of cross-browser support etc..

I've been using AJAX with jQuery and it seems easy, but I'm unsure of the differences,

I've read I can also use this to get the data:

$.ajax({
  url: url,
  dataType: 'json',
  data: data,
  success: callback
});

Can anyone explain the difference between making a jQuery AJAX request using JSON and making a jQuery AJAX request without the json type?

Will the answer be ok for all browsers?

Answer 1

I think you are confusing the terms.

AJAX stands for Asynchronous Javascript and XML, which is a mechanism used to launch asynchronous HTTP requests to a server using JavaScript. Don't let the name fool you; there's no restriction on you only retrieving JavaScript or XML from this technique. You can quite happily return other data formats as well (HTML, plain text and JSON, to list a few).

JSON is just one of these formats. It's a data interchange format, where-as AJAX is a technique to communicate with a server after the initate page load has completed.

To answer your question on whether you need to specify the dataType; jQuery will best guess the response format (be it HTML or JSON etc), so you're usually fine to omit it.