Question

I am looking for a typical example where calling the jQuery function getJSON offers a large advantage over using standard AJAX functions (from jQuery or from native JavaScript).

Answer 1

It’s shorter. Basically .getJSON is just a shortcut for jQuerys

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

Which now you only do

$.getJSON(url, calllback);

The advantage over using plain AJAX should be fairly obvious as it is a lot less to type and takes care of all the annoying browser specific differences.