This HTML4 attribute was intended to defer/delay execution of specific javascript code until after the page is rendered. In theory, this makes the website “appear” faster as the functions relevant to the User-Interface can be executed before other “background” processes that would otherwise block the screen from displaying.


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


NOTE: Do not use defer for external scripts that might depend on each other if you need to support MSIE9 and earlier.

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