How to defer parsing javascript

[trihung]

I was add defer to code but it is not validation. Anyone help me, please ?
My code:
<script src=" http://example.com/ demo_defer.js" defer> </script>

[edited by: bill at 7:42 am (utc) on Apr 1, 2013]
[edit reason] Use example.com [/edit]

[daveVk]

If validating as xhtml use

<script src="example.js" defer="defer"></script>

[ergophobe]

Try using asynchronous loading with LABjs, head.js, control.js or something like that. This will speed up the feel a lot, everything will load as quickly as possible and run as soon as ready.

One caveat: you can't do asynch loading on anything that uses document.write()