how does getjson work? code example

Example 1: how does getjson work?

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

Example 2: how does getjson work?

{
  "one": "Singular sensation",
  "two": "Beady little eyes",
  "three": "Little birds pitch by my doorstep"
}

Example 3: how does getjson work?

$.getJSON( "ajax/test.json", function( data ) {
  var items = [];
  $.each( data, function( key, val ) {
    items.push( "<li id='" + key + "'>" + val + "</li>" );
  });
 
  $( "<ul/>", {
    "class": "my-new-list",
    html: items.join( "" )
  }).appendTo( "body" );
});