Now it’s been some time since HTML5 came on the scene. It’s shiny new glean has been replaced with a well worn veneration and stability.
Although it’s made some marked improvements over its predecessors in terms of not requiring laboured attributes or overly strict syntax, one of its tenets means a certain level of backward compatibility still exists. And owing to the certain habits or strict requirements in the past, some developers simply would’ve stuck to those habits or not realised that with the latest iteration, that some items were no longer needed. This lists the obvious, and not so obvious items.
This is the most obvious one and one which is required. So, without delving into all the iterations and variances, the last two major branches, XHTML and HTML 4 series required a lengthy declaration of the schemas used for the document type defintion (DTD). HTML5 did away with all the cumbersome description and replaced it with the all too popular and well received
Linking to external files
HTML5 enables asynchronous loading of scripts without locking the other processes from loading in a browser. This is done by using the async tag
<sript src="js/script.js" async></script>
How? By using the async attribute preventing users from having to worry about script link placement and all the consequences the decision imbues.
Defer is similar to the Async attribute, however, it can be used when multiple scripts are needed and should be loaded in order. Scripts with this attribute will wait to execute until the page has finished loading.
These are some of the enhancements for the moment. If there are ones that I have missed, especially major ones, let me know in the comments.