Question

My fiddle link is

http://jsfiddle.net/tBYdu/18/

and I don’t understand why when I push button it deletes all following <li> instead of deleting only the selected <li> by ID?

Answer 1

That happens because you apply the click handlers to all buttons..

$('button') will get applied to all buttons that are present in the html..

Try a single

$('ul').on('click','button', function(){
   $(this).closest('li').remove();
});

Demo at http://jsfiddle.net/tBYdu/29/