Asks for 10 numbers, then adds them together.

numberadd.html

<script>
var num = [];
var total = 0;
for (var i = 0; i < 10; i++) {// for i as each number between 0 and 9:
	num.push(parseInt(prompt()));// ask for a number
}
for (i=0; i < num.length; i++){// for i as each number in num.length:
	total += num[i];// total equals itself plus the current number in num
}
</script>