Post Increment
new value of a 10
Code
<script type="text/javascript">
var a=10;
document.write("new value of a"+(a++));//+ for concat
</script>
Pre Increment
new value of a 11
Code
<script type="text/javascript">
var a=10;
document.write("new value of a"+(++a));//+ for concat
</script>