CODE EXAMPLE FOR JAVASCRIPT

javascript encriment +1

<span id="counter">0</span>
<pre id="my-pre">test</pre>

<script>
    var counter = 0,
        counterSpan = document.getElementById('counter');

    //add the click listener using addEventListener, this is preferred over inline handlers
    document.getElementById('my-pre').addEventListener('click', function () {
        counterSpan.innerHTML = ++counter;
    });
</script>