document the wire type of parameter of data of function jQuery.post()

What is the wire type of parameter of data of jQuery.post()?
If I pass in an object like {"n":"bar"} , what I will get in the ajax http post body? a json like '{"n":"bar"}' or a url-encoding query like "n=bar" ?
If I pass in a string like "hello world", what I will get in the ajax http post body? Direct put in http post body?

The document at https://api.jquery.com/jquery.post/ do not tell me anything about it.

notice

• I can write a web server and use the jquery.post() to try and guess what will happen, but I want know it before I write my web server logic.
• Parameter dataType is The type of data expected from the server. , not the request data type.
• I have found some details in https://github.com/jquery/jquery/issues/2594#issuecomment-140113401 . But it is hard to find in google and it is not all the problem.

Start with the jQuery.post() API page linked in the issue and read the related details in jQuery issue #2594. Document what request body is produced when data is an object versus a string, including how dataType differs; the page is done when these cases are answered directly.