$("#draggable").draggable({ snap: true });
$("#draggable2").draggable({ snap: '.ui-widget-header' });
$("#draggable3").draggable({ snap: '.ui-widget-header', snapMode: 'outer' });
$("#draggable4").draggable({ grid: [20,20] });
$("#draggable5").draggable({ grid: [80, 80] });