<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
$('#hideshow').click(function(){
$('#content').toggle('show');
});
});
</script>
And the html
<div id='content'>Hello World</div>
<input type='button' id='hideshow' value='hide/show'>