$(function() {

  var body = $('body');

  var backgrounds = [

    '//placehold.it/800x600/cf5&text=1',

    '//placehold.it/800x600/f1f&text=2',

    '//placehold.it/800x600/333&text=3',

    '//placehold.it/800x600/0f0&text=4',

    '//placehold.it/800x600/70f&text=5'

  ];

  var current = 0;

  // Preload all images

  for(var i=0; i<backgrounds.length; i++){

    var img = new Image();

    img.src= backgrounds[i];

  }

  function nextBackground() {

    body.css(

      "background-image",

      "url("+backgrounds[++current % backgrounds.length]+")"

    );

    setTimeout(nextBackground, 5000);

  }

  setTimeout(nextBackground, 5000);

  body.css("background-image", "url("+backgrounds[0]+")");

});