jquery: textarea - 'Write a comment...' and 'What's on your mind?' like facebook

Hi,

I would like to know how to make a textarea like the ones in facebook, which they always have default text 'Write a comment...' or 'What's on your mind?' - they will disappear when u click on the textarea, but they will change back to default when u click outside the textarea again...

hope you understand i am trying to explain above.

any online references please...?

many thanks,
Lau

It does not seem to make much sense to revert to the default text as soon as the user clicks elsewhere in the document.


<textarea id = "txt1" rows = "6" cols = "25" onclick = "erase()">Write a comment......</textarea>

<script type = "text/javascript">
var flag = true;
function erase() {
if (flag) {
document.getElementById("txt1").value = "";
flag = false;
}
}
</script>


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